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A particle of mass m moving eastward with a speed v collides with another particle of the same mass moving northwards with same speed v. The two particles coalesce on collision. The new particle of mass 2 m will move with velocity

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Important Questions on Work, Energy and Power

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Two perfectly elastic particles A and B of equal masses travelling along the line joining them with velocity 15 m s-1 and 10 m s-1 respectively, collide. Their velocities after the elastic collision will be (in m s-1 ), respectively
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If the magnitude of two vectors are 8 unit and 5 unit and their scalar product is zero, the angle between the two vectors is
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In which of the following figures the work done by force F in displacing an object through distance d is positive? ( (θ is the angle between F and d)
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The figure given below shows the force F versus displacement x graph. The net work done by the force when an object is displaced from x=0 to x=16 m is

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A bullet having mass 10 g is fired towards a fixed wooden block with velocity of 30 m s-1. If it comes out of the block with velocity of 20 m s-1, then the total work done by the resistive forces is
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A force F=(3i^+4j^+5k^)N acts on an object and displaces it through d=5k^ m. The total work done by the force in this process is
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Two balls, one of mass m and other of mass 2 m are moving towards each other with respective speeds of 10 m s-1 and 20 m s-1 on a smooth horizontal floor. If after collision they stick to each other and move as combined mass (perfectly inelastic collision), then the speed of combined mass will be
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A ball is dropped from 100 m and it rebounds to a height of 70 m. The percentage loss of energy is