1) Work done will be maximum if the angle between the force F and displacement d is a. 45? b. 90? c. 180? d. 0?
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2) A field in which the work done in a moving a body along closed path is zero is called a. electric field b. conservative field c. electromagnetic field d. gravitational field
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3) When a force is parallel to the direction of motion of the body, then work done on the body is a. zero b. minimum c. infinity d. maximum
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4) Which of the following types of force can do no work on the particle on which it acts? a. frictional force b. gravitational force c. elastic force d. centripetal force
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5) If a body a mass of 2 kg is raised vertically through 2m, then the work done will be a. 38.2 J b. 392.1 J c. 39.2 J d. 3.92 J
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6) An elevator weighing 3.5 x 10-6 N is raised to a height of 1000 m in the absence of friction, the work done is a. 3.5 x 103 J b. 3.5 x 104 J c. 3.5 x 106 J d. 3.5 x 109 J
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7) The average power and instantaneous power become equal if work is done at a. any rate b. at variable rate c. at uniform rate d. at high rate
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8) The relation between horse power and watt is a. 1 hp = 546 watts b. 1 hp = 746 watts c. 1 hp = 1000 watts d. 1 hp = 946 watts
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9) Proton electron neutron and a particles have same momentum. Which of them have highest K.E? a. Proton b. electron c. neutron d. a-particle
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10) Slope of work time graph is equal to a. displacement b. acceleration c. power d. energy
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11) Work done by variable force is determine by dividing a. force into small interval b. displacement into small interval c. both force and displacement into small intervals d. force into small and displacement into large intervals
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12) Work done on the body equals to the a. change in its K.E always b. change in its P.E always c. change in its K.E and change in its P.E d. neither change in K.E and nor change in its P.E
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13) The escape velocity of a body in gravitational field of earth is independent of a. its mass b. the angle at which it is thrown c. both its mass and the angle at which it is thrown d. gravitational field of earth
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14) The tides raise the mater in the see roughly in a day a. once b. twice c. four time d. eight time
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15) The source of geothermal energy is a. decay of radioactive element in the earth b. compression of material in the earth c. residual lost of the earth d. all as said in a - b and c
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16) The highest value of escape velocity in solar system is planet a. Earth b. Neptune c. Jupiter d. Moon
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17) Work done by the force of friction is a. always positive b. always negative c. positive only for small frictional force d. positive only for large frictional force
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18) Gravitational P.E of a body has a. no formula b. a formula mgh only c. a formula d. no general formula
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19) If velocity is doubled then a. momentum increases 4 times and K.E increases 2 times b. momentum and K.E. remain same c. momentum increases 2 times and K.E increases constant d. momentum increases 2 times and K.E increases 4 time
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20) When the speed of a moving body is doubled then a. its K.E is doubled b. its acceleration is doubled c. its P.E is doubled d. its momentum is doubled
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21) One mega watt hour is equal to a. 36 x 106 J b. 36 x 1012 J c. 36 x 109 J d. 36 x 108 J
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22) Which of the following is not conservative force a. friction b. electric c. gravitational d. magnetic
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23) Work has the dimension as that of same as that of a. torque b. angular momentum c. linear momentum d. power
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24) The consumption of energy by a 60 watt bulb in 2 sec is a. 120 J b. 60 J c. 30 J d. 0.02 J
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25) The relation between the escape velocity V esc and orbital speed Vo is given by a. V esc = 1/2Vo b. V esc = ?2 Vo c. V esc = Vo d. V esc = 2Vo
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26) The escape velocity form the earth surface in km S-1 is a. 4.2 km S-1 b. 7.5 km S-1 c. 9.5 km S-1 d. 1.1 km S-1
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27) If moon radius is 1600 km and g on its surface is 1.6 ms-2 then the escape velocity on the moon is a. 1600 ms-1 b. 50.6 ms-1 c. 71.6 ms-1 d. 2263ms-1
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28) When two protons are brought together a. Kinetic energy increases b. P.E. between them increases c. P.E. between them decreases d. P.E. between tem does not change
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29) When arrow is released form its bow, its energy is transformed from a. heat energy to K.E b. elastic P.E to K.E c. elemical energy to elastic P.E d. K.E to elastic P.E.
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30) A man lifts vertically a weight of 40kg through 1m in 10s; while a chile lifts vertically a weight of 10kg through a distance of 1m in 1s. What will be correct inference? a. man does more work than child b. child does more work than man c. both do the same amount of work d. it is a foolish question
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31) The work done by friction is a. positive b. negative c. zero d. none of these
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32) The area under the force displacement graph represents a. area b. work done c. power d. none of these
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33) The dimension of power is a. [ML2T-3] b. [ML2T-2] c. [ML2T3] d. none of these
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34) Propulsion force of a rocket is a. non-conservative force b. conservative force c. both (a) and (b) d. non of these
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35) The dot product of force and velocity is a. power b. work c. impulse d. torque
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36) Geothermal energy is a ____________________ source of energy. a. non-renewable b. stable c. renewable d. none of the above
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37) The source of tidal energy is a. sun b. earth c. both (a) and (b) d. moon
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38) ________________ cells converts solar energy into electrical energy a. rotory b. photovoltaic c. galvanic d. non of these
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39) On a clear day at noon the solar energy reaching the earth is a. 1.44kw/m2 b. 1.4kw/m2 c. 1 kw/m2 d. none
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40) Biomass can be converted into fuels by a. direct combustion b. fermentation c. both (a) and (b) d. none of these
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