# In the given curved road, if particle is released from  then a) Kinetic energy at  must be b) Kinetic energy at  may be zero c) Kinetic energy at  must be less than d) Kinetic energy at  must not be equal to zero

## Question ID - 50852 :- In the given curved road, if particle is released from  then a) Kinetic energy at  must be b) Kinetic energy at  may be zero c) Kinetic energy at  must be less than d) Kinetic energy at  must not be equal to zero

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(b)

1. If the surface is smooth then the kinetic energy at  never be zero

2. If the surface is rough, the kinetic energy at  be zero. Because, work done by force of friction is negative. If work done by friction is equal to  then, net work done on body will be zero. Hence, net change in kinetic energy is zero. Hence, (b) is correct

3. If the surface is rough, the kinetic energy at  must be lesser than . If surface is smooth, the kinetic energy at  is equal to

4.The reason is same as in (a) and (b)

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