View note:Physics-CBSE-class-10



Questions of this subject!.

QuestionLikes!Dislikes!Answers!
1)State the laws of reflection. -CBSE physics

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2)Differentiate between convex mirror and concave mirror. -CBSE Physics

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3)Explain the following terms -CBSE Physics

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4)Explain the Image Formation in Spherical Mirrors .-CBSE Physics

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5)Explain the representation of Images Formed by Spherical Mirrors Using Ray Diagrams. CBSE Physics

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6)Explain the representation of Images Formed by concave Mirrors Using Ray Diagrams. CBSE Physics

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7)Explain the representation of Images Formed by convex Mirrors Using Ray Diagrams. CBSE Physics

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8)Explain the radius of curvature in concave . CBSE Physics

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9)Explain the Sign Convention for Reflection by Spherical Mirrors. CBSE Physics

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10)Explain the formula for magnification. -CBSE Physics

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11)A convex mirror used for rear-view on an automobile has a radius of curvature of 3.00 m. If a bus is located at 5.00 m from this mirror, find the position, nature and size of the image. -CBSE Physics

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12)An object, 4.0 cm in size, is placed at 25.0 cm in front of a concave mirror of focal length 15.0 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Find the nature and the size of the image. -CBSE Physic

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13)Find the focal length of a convex mirror whose radius of curvature is 32 cm. -CBSE Physics

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14)A concave mirror produces three times magnified (enlarged) real image of an object placed at 10 cm in front of it. Where is the image located? -CBSE Physics

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15)State the laws of refraction. -CBSE Physics

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16)What is refractive index? -CBSE Physics

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17)A ray of light travelling in air enters obliquely into water. Does the light ray bend towards the normal or away from the normal? why? -CBSE Physics

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18)The refractive index of diamond is 2.42. What is the meaning of this statement? -CBSE Physics

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19)Explain the Image Formation in Spherical lenses .-CBSE Physics

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20)Explain the Image Formation in Spherical lenses using the ray diagrams.-CBSE Physics

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21)A concave lens has focal length of 15 cm. At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens? Also, find the magnification produced by the lens. -CBSE Physics

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22)A concave lens has focal length of 15 cm. At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens? Also, find the magnification produced by the lens. -CBSE Physics

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23)A 2.0 cm tall object is placed perpendicular to the principal axis of a convex lens of focal length 10 cm. The distance of the object from the lens is 15 cm. Find the nature, position and size of the image. Also find its magnification. -CBSE Physics

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24)Define 1 dioptre of power of a lens. -CBSE Physics

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25)A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens. -CBSE Physics

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26)Find the power of a concave lens of focal length 2 m. -CBSE Physics

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27) Which one of the following materials cannot be used to make a lens? -CBSE Physics

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28) A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram. -CBSE Physics

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29) An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed. -CBSE Physics

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30) An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image. -CBSE Physics

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31)The magnification produced by a plane mirror is +1. What does this mean? -CBSE Physics

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32)An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size -CBSE Physics

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33) An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed, so that a sharp focussed image can be obtained? Find the size and the nature of the image. -C

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34) Find the focal length of a lens of power – 2.0 D. What type of lens is this? -CBSE Physics

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35)What is Myopia? -CBSE Physics

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36)What is Hypermetropia? -CBSE Physics

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37)What is Presbyopia? -CBSE Physics

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38)What is meant by power of accommodation of the eye? -CBSE Physics

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39)A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of the corrective lens used to restore proper vision? -CBSE Physics

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40)What is the far point and near point of the human eye with normal vision? -CBSE Physics

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41)A student has difficulty reading the blackboard while sitting in the last row. What could be the defect the child is suffering from? How can it be corrected? -CBSE Physics

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42) Explain why the planets do not twinkle. -CBSE Physics

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43)Why do stars twinkle? -CBSE Physics

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44)What happens to the image distance in the eye when we increase the distance of an object from the eye? -CBSE Physics

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45) Why is a normal eye not able to see clearly the objects placed closer than 25 cm? -CBSE Physics

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46)Make a diagram to show how hypermetropia is corrected. The near point of a hypermetropic eye is 1 m. What is the power of the lens required to correct this defect? Assume that the near point of the normal eye is 25 cm. -CBSE Physics

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47) The far point of a myopic person is 80 cm in front of the eye. What is the nature and power of the lens required to correct the problem? - CBSE physics

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48)A current of 0.5 A is drawn by a filament of an electric bulb for 10 minutes. Find the amount of electric charge that flows through the circuit. -CBSE Physics

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49)What does electric circuit mean? -CBSE Physics

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50)What is meant by Potential difference?-CBSE Physics

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51)Calculate the number of electrons constituting one coulomb of charge.-CBSE Physics

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52)What is mean by voltmeter? -CBSE Physics

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53)How much work is done in moving a charge of 2 C across two points having a potential difference 12 V? -CBSE Physics

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54)what is mean by voltmeter -CBSE Physics

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55)what is mean by voltmeter -CBSE Physics

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56)Name a device that helps to maintain a potential difference across a conductor-CBSE Physics

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57)What is meant by saying that the potential difference between two points is 1 V? -CBSE Physics

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58)How much energy is given to each coulomb of charge passing through a 6 V battery? -CBSE Physics

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59)What is meant by Ohm’s law? -CBSE Physics

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60)The potential difference between the terminals of an electric heater is 60 V when it draws a current of 4 A from the source. What current will the heater draw if the potential difference is increased to 120 V? -CBSE Physics

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61)Resistance of a metal wire of length 1 m is 26 Ω at 20°C. If the diameter of the wire is 0.3 mm, what will be the resistivity of the metal at that temperature?Predict the material of the wire. -CBSE Physics

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62)A 4 Ω resistance wire is doubled on it. Calculate the new resistance of the wire.-CBSE Physics

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63)On what factors does the resistance of a conductor depend? -CBSE Physics

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64)Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?-CBSE Physics

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65)Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it? -CBSE Physics

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66)Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal? -CBSE Physics

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67)Which among iron and mercury is a better conductor? -CBSE Physics

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68)R1 = 10 Ω, R2 = 40 Ω, R3 = 30 Ω, R4 = 20 Ω, R5 = 60 Ω, and a 12 V battery is connected to the arrangement. Calculate (a) the total resistance in the circuit, and (b) the total current flowing in the circuit-CBSE Physics

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69)An electric iron consumes energy at a rate of 840 W when heating is at the maximum rate and 360 W when the heating is at the minimum. The voltage is 220 V. What are the current and the resistance in each case? -CBSE Physics

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70)Judge the equivalent resistance when the following are connected in parallel – (a) 1 Ω and 106 Ω, (b) 1 Ω and 103 Ω, and 106 Ω. -CBSE Physics

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71)How can three resistors of resistances 2 Ω, 3 Ω, and 6 Ω be connected to give a total resistance of (a) 4 Ω, (b) 1 Ω? -CBSE Physics

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72)What is (a) the highest, (b) the lowest total resistance that can be secured by combinations of four coils of resistance 4 Ω, 8 Ω, 12 Ω, 24 Ω? -CBSE Physics

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73)100 J of heat are produced each second in a 4 Ω resistance. Find the potential difference across the resistor. -CBSE Physics

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74)Why does the cord of an electric heater not glow while the heating element does? -CBSE Physics

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75)Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V -CBSE Physics

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76)An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s. -CBSE Physics

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77)Explain the termed electric power -CBSE Physics

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78)What is ampere? -CBSE Physics

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79)An electric bulb is connected to a 220 V generator. The current is 0.50 A. What is the power of the bulb? -CBSE Physics

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80)An electric refrigerator rated 400 W operates 8 hour/day. What is the cost of the energy to operate it for 30 days at Rs 3.00 per kW h? -CBSE Physics

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81)What determines the rate at which energy is delivered by a current? -CBSE Physics

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82)An electric motor takes 5 A from a 220 V line. Determine the power of the motor and the energy consumed in 2 h. -CBSE Physics

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83)What is electrical energy dissipated . -CBSE Physics

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84) When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor. -CBSE Physics

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85) A battery of 9 V is connected in series with resistors of 0.2 Ω, 0.3 Ω, 0.4 Ω , 0.5 Ω and 12 Ω, respectively. How much current would flow through the 12 Ω resistor -CBSE Physics

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86)How many 176 Ω resistors (in parallel) are required to carry 5 A on a 220 V line? -CBSE Physics

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87)Show how you would connect three resistors, each of resistance 6 Ω, so that the combination has a resistance of (i) 9 Ω, (ii) 4 Ω. -CBSE Physics

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88) Several electric bulbs designed to be used on a 220 V electric supply line, are rated 10 W. How many lamps can be connected in parallel with each other across the two wires of 220 V line if the maximum allowable current is 5 A? -CBSE Physics

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89)A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What are the currents in the three cases? -CBSE Physics

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90) Two lamps, one rated 100 W at 220 V, and the other 60 W at 220 V, are connected in parallel to electric mains supply. What current is drawn from the line if the supply voltage is 220 V? -CBSE Physics

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91) Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes? -CBSE Physics

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92)Why is the tungsten used almost exclusively for filament of electric lamps?. -CBSE Physics

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93)Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?. -CBSE Physics

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94)Why is the series arrangement not used for domestic circuits?. -CBSE Physics

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95)How does the resistance of a wire vary with its area of cross-section?. -CBSE Physics

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96)Why are copper and aluminium wires usually employed for electricity transmission?. -CBSE Physics

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97)What is a good source of energy?. -CBSE Physics

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98)What is a good fuel?. -CBSE Physics

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99)If you could use any source of energy for heating your food, which one would you use and why?. -CBSE Physics

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100)What are the disadvantages of fossil fuels?. -CBSE Physics

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101)Why are we looking at alternate sources of energy?. -CBSE Physics

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102)Can any source of energy be pollution-free? Why or why not?. -CBSE Physics

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103)Hydrogen has been used as a rocket fuel. Would you consider it a cleaner fuel than CNG? Why or why not?. -CBSE Physics

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104)Name two energy sources that you would consider to be renewable. Give reasons for your choices. -CBSE Physics

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105)Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices. -CBSE Physics

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106) What are the environmental consequences of the increasing demand for energy? What steps would you suggest to reduce energy consumption? -CBSE Physics

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107)What are the advantages and disadvantages of using a solar cooker? Are there places where solar cookers would have limited utility? -CBSE Physics

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108)What are the qualities of an ideal source of energy? -CBSE Physics

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109)Compare and contrast fossil fuels and the Sun as direct sources of energy. -CBSE Physics

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110) Compare and contrast bio-mass and hydro electricity as sources of energy. -CBSE Physics

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111)Why are some substances biodegradable and some non-biodegradable? -CBSE Physics

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112)Give any two ways in which biodegradable substances would affect the environment. -CBSE Physics

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113)Give any two ways in which non-biodegradable substances would affect the environment.-CBSE Physics

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114)What are trophic levels? Give an example of a food chain and state the different trophic levels in it.-CBSE Physics

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115)What is ozone and how does it affect any ecosystem?.-CBSE Physics

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116)How can you help in reducing the problem of waste disposal? Give any two methods?.-CBSE Physics

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117) Why is damage to the ozone layer a cause for concern? What steps are being taken to limit this damage?.-CBSE Physics

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118) If all the waste we generate is biodegradable, will this have no impact on the environment?.-CBSE Physics

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119)What is biological magnification? Will the levels of this magnification be different at different levels of the ecosystem?.-CBSE Physics

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120) What are the problems caused by the non-biodegradable wastes that we generate? ?.-CBSE Physics

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121)What is magnification? -CBSE physics

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122)Name a metal which offers higher resistance to the passage of electricity than copper. -2005 CBSE physics Class 10

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123) Where will the image be formed by concave mirror when an object is placed between the pole and the focus point of the mirror ? -2005 CBSE Physic class 10

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124)Which has a higher resistance : a 50 W lamp bulb or a 25 W lamp bulb and how many times ? -2005 CBSE Physic class 10

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125)Draw diagrams to distinguish between equatorial orbit and polar orbit of artificial satellites of earth -2005 CBSE Physic class 10

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126)With respect to air the refractive indices of water and benzene are 1.33 and 1.50 respectively. Calculate the refractive index of benzene with respect to water. -2005 CBSE Physic class 10

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127)A torch bulb is rated 2.5 V and 750 mA. Calculate (i) its power, (ii) its resistance and (iii) the energy consumed if this bulb is lighted for 4 hours. -2005 CBSE Physic class 10

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128)Describe briefly the Big Bang Theory of the origin of universe -2005 CBSE Physic class 10

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129)Explain the following terms used in relation to defects in vision and corrections provided for them -2005 CBSE Physic class 10

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130)Describe with a ray diagram how a person with myopia can be helped by spectacles. -2005 CBSE Physic class 10

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131)What is a simple microscope ? Draw diagrams to show the image formed by a simple microscope with the eye focussed -2005 CBSE Physic class 10

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132) What is the maximum magnification obtainable by a simple microscope ? -2005 CBSE Physic class 10

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133)What are magnetic field lines ? How is the direction of a magnetic field at a point determiend ? -2005 CBSE Physic class 10

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134)Draw two field lines around a bar magnet along its length on its two sides and mark the field directions on them by arrow marks. -2005 CBSE Physic class 10

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135)List any three properties of magnetic field lines. -2005 CBSE Physic class 10

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136)What constitutes the field of a magnet? -2006 CBSE Physic class 10

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137)What is the advantage of the third wire of earth connection in domestic electric appliances? - 2006 CBSE Physic class 10

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138)Name the process of large energy production in the Sun. -2006 CBSE Physic class 10

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139)What is efflorescence? Give an example. -2006 CBSE Physic class 10

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140)Draw a ray diagram to show the -2006 CBSE Physic class 10

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141)If you observe the position of a star at a fixed time everyday, how many degrees higher will it appear after a month of 30 days? - 2006 CBSE Physic class 10

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142)Describe an activity to show that a star moves a certain angle in the sky relative to its position the previous day. 2006 CBSE Physic class 10

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143) A 5.0 cm tall object is placed per pendicular to the principal axis of a convex lens of focal length 20 cm. The distance of the object from the lens is 30 cm. By calculation determine (i) the position, and (ii) the size of the image formed. - 2006

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144)Distinguish between renewable and non-renewable sources of energy giving one example of each. 2006 CBSE Physic class 10

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145) Why is the use of wood as a fuel not advised although forests can be replenished? -2006 CBSE Physic class 10

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146)Write the value of solar constant of Sun. - 2006 CBSE Physic class 10

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147)What type of mirror is used in Box Type Solar Cooker? 2006 CBSE Physic class 10

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148)Why it is difficult to use hydorgen as a source of energy? - 2006 CBSE Physic class 10

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149)What is the maximum temperature attained in a concave reflector type solar cooker? - 2006 CBSE Physic class 10

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150)Fossil fuels are classified as non renewable source of energy. Explain why. - 2006 CBSE Physic class 10

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151)What is a Galaxy ? -2007 CBSE Physic class 10

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152) What is the S.I. unit of electric potential ? - 2007 CBSE Physic class 10

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153)Distinguish between polar and equatorial orbits for artificial satellites. Illustrate the two orbits on a diagram -2007 CBSE Physic class 10

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154)An electric iron has a rating of 750 W, 220 V. Calculate -2007 CBSE Physic class 10

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155)A concave lens has focal length of 20 cm. At what distance from the lens a 5 cm tall object be placed so that it forms an image at 15 cm from the lens ? Also calculate the size of the image formed -2007 CBSE Physic class 10

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156)Why is the Solar Cooker box covered with a plane glass plate ?2007 CBSE Physic class 10

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157)Why is energy of water flowing in a river considered to be an indirect form of Solar energy ? - 2007 CBSE Physic class 10

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158)What is meant by ‘Electric Resistance’ of a conductor ? -2007 CBSE Physic class 10

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159)A wire of length L and resistance R is stretched so that its length is doubled and the area of cross-section is halved. How will its : 2007 CBSE Physic class 10

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160) Define the term, ‘Critical Angle’. - 2007 CBSE Physic class 10

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161) What is meant by ‘total internal reflection’ ? - 2007 CBSE Physic class 10

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162)State two essential conditions for total internal reflection to take place. With the help of a ray diagram, illustrate an application of total internal reflection -2007 CBSE Physic class 10

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163) What is meant by a ‘magnetic field’ ? -2007 CBSE Physic class 10

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164)How is the direction of magnetic field at a point determined -2007 CBSE Physic class 10

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165)Describe an activity to demonstrate the direction of the magnetic field generated around a current carrying conductor - 2007 CBSE Physic class 10

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166) What is the direction of magnetic field at the centre of a current carrying circular loop ? -2007 CBSE Physic class 10

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167)Draw a ray diagram to show the refraction of light through a glass prism. Mark on it - 2008 CBSE Physic class 10

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168)Draw a ray diagram to show the refraction of light through a glass prism. Mark on it -2008 CBSE Physic class 10

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169)Draw a ray diagram to show the refraction of light through a glass prism. Mark on it - 2008 CBSE Physic class 10

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170)Give two examples each of the following :-2008 CBSE Physic class 10

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171)List any, four reasons for vegetative propagation being practised in the growth of some type of plants. 2008 CBSE Physic class 10

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172)Explain with the help of a diagram, how we are able to observe the sunrise about two minutes before the sun gets above the horizon. -2008 CBSE Physic class 10

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173)An object is placed between infinity and the pole of a convex mirror. Draw a ray diagram and also state the position, the relative size and .the nature. of the image formed. -2008 CBSE Physic class 10

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174)What is the principle of reversibility of light? -2008 CBSE Physic class 10

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175)Show that the incident ray of light is parallel to the emergent ray of light then light falls obliquely on a side of a rectangular glass slab. -2008 CBSE Physic class 10

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176)What eye defect is myopia ? 2008 CBSE Physic class 10

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177)Describe with a neat diagram how this defect of vision can be corrected by using a suitable lens. -2008 CBSE Physic class 10

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178)What is meant by power of a lens ? -2008 CBSE Physic class 10

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179)State and define the S.l. unit of power of a lens. 2008 CBSE Physic class 10

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180)A convex lens of focal length 25 cm and a concave lens of focal length 10 cm are placed in close contact with each other. Calculate the lens power of this combination. - 2008 CBSE Physic class 10

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181) Draw a ray diagram to show the formation of image of an object placed between infinity and the optical centre of a concave lens. -2008 CBSE Physic class 10

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182) A concave lens of focal length 15 em forms an image 10 em from the lens. Calculate -2008 CBSE Physic class 10

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183)A ray of light LM is incident on a mirror as shown in the figure. The angle of incidence for this ray is the angle between it and the line joining two other points in the figure. Name these two points. -2009 CBSE Physic class 10

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184) The following table gives the values of refractive indices of a few media. 2009 CBSE Physic class 10

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185) Why potato chips manufacturers fill the packet of chips with nitrogen gas? - 2009 CBSE Physic class 10

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186) Alloys are used in electrical heating devices rather than pure metals. Give one reason -2009 CBSE Physic class 10

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187)A student has been collecting silver coins and copper coins. One day she observed a black coating on silver coins and a green coating on copper coins. Which chemical phenomenon is responsible for these coatings? 2009 CBSE Physics class 10

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188)Two students perform the experiments on series and parallel combinations of two given resistors R1 and R2 and plot the following V-I graphs. 2009 CBSE Physic class 10

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189)Draw the pattern of magnetic field lines of a current carrying solenoid. What does the pattern of field lines inside the solenoid indicate? -2009 CBSE Physic class 10

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190) Write one application of magnetic field of current carrying solenoid. 2009 CBSE Physic class 10

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191) A student finds the writing on the blackboard as blurred and unclear when sitting on the last desk in the classroom. He however, sees it clearly when sitting on the front desk at an approximate distance of 2m from the blackboard. Draw ray diagrams t

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192)In a household electric circuit different appliances are connected in parallel to one another. Give two reasons. 2009 CBSE Physic class 10

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193)2009 CBSE Physic class 10

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194)You are given following current-time graphs from two different sources: 2009 CBSE Physic class 10

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195) A ray of light AM is incident on a spherical mirror as shown in the diagram. -CBSE physics class 10

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196)The ciliary muscles of a normal eye are in their (i) most relaxed (ii) most contracted state. In which of the two cases is the focal length of the eye-lens more? -CBSE physics class 10

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197) Tap water conducts electricity whereas distilled water does not. Why? - CBSE physics class 10

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198)An electric geyser has the ratings 2000W, 220V marked on it. What should be the minimum rating, in whole number of a fuse wire, that may be required for safe use with this geyser?-CBSE physics class 10

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199)Two metallic wires A and B of the same material are connected in parallel. Wire A has length l and radius r, wire B has a length 2l and radius 2r. Compute the ratio of the total resistance of parallel combination and the resistance of wire A. -CBSE p

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200) A student performs an experiment to study the magnetic effect of current around a current carrying straight conductor. He reports that -CBSE physics class 10

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201)A beam of white light falling on a glass prism gets split up into seven colours marked 1 to 7 as shown in the diagram -CBSE physics class 10

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202)A concave mirror produces three times enlarged image of an object placed at 10 cm infront of it. Calculate the radius of curvature of the mirror. -CBSE physics class 10

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203) The electric power consumed by a device may be calculated by using either of the two expressions -CBSE physics class 10

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204)Why is tungsten used almost exclusively for filament of electric lamps? - CBSE physics class 10

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205)Why are copper and aluminium wires usually used for electricity transmission? -CBSE physics class 10

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206)Explain the meaning of the word ‘electromagnetic’ and ‘induction’ in the term electromagnetic induction. On what factors does the value of induced current produced in a circuit depend? Name and state the rule used for determination of directi

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207)You are give three resistors of 10 Ω, 10 Ω and 20 Ω, a battery of emf 2.5V, a key, an ammeter and a voltmeter. Draw a circuit diagram showing the correct connections of all given components such that the voltmeter gives a reading of 2.0V. CBSE phy

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208)Sketch magnetic field lines arround a current carrying straight conductor. -CBSE physics class 10

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209)The electrical resistivity of few materials is given below in ohm-meter. Which of these materials can be used for making element of a heating device? -CBSE physics class 10

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210)Refractive index of media A, B, C and D are - CBSE physics class 10

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211)A household uses the following electric appliances -CBSE physics class 10

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212) What is the meaning of the term ‘frequency’ of an alternating current? What is its value in India? -CBSE physics class 10

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213)Why is an alternating current considered to be advantageous over direct current for long range transmission of electric energy? -CBSE physics class 10

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214) A person is able to see objects clearly only when these are lying at distances between 50cm and 300cm from his eye. -CBSE physics class 10

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215)Why does a current carrying conductor kept in a magnetic field experience force? what factors does the direction of this force depend? Name and state the rule used for determination of direction of this force. -CBSE physics class 10

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216)The sky appears to be blue during day time to a person on earth. WHY? -CBSE physics class 10

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217)The sky near the horizon appears to have a reddish heu at the time of sunset and sunrise. WHY? -CBSE physics class 10

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218)The sky appears dark instead of blue to an astronaut. WHY? -CBSE physics class 10

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219)The stars appears to twinkle. WHY?-CBSE physics class 10

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220)The planets do not twinkle. WHY? -CBSE physics class 10

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221)An object of size 5 cm is kept at a distance of 25cm from the optical centre of a converging lens of focal length 10cm. Calculate the distance of the image from the lens and size of the image. -CBSE physics class 10

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222)An automobile vehicle has a mass of 1500 kg. What must be the force between the vehicle and road if the vehicle is to be stopped with a negative acceleration of 1.7 m s-2? - Physics Cbse class 11

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