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Question
A block weighing 10 N travels down a smooth curved track AB joined to a rough horizontal surface (In the following figure). The rough surface has a friction coefficient of 0⋅20 with the block. If the block starts slipping on the track from a point 1⋅0 m above the horizontal surface, how far will it move on the rough surface?
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Solution
Given,
\[\text{ Friction coefficient, } \mu = 0 . 2\]
\[\text{ Initial height of the block, H = 1 m }\]
\[\text{ Initial velocity = Final velocity }= 0\]
Potential energy of the block at the top of the curved track = Kinetic energy of the block at the bottom of the track
\[\Rightarrow \text{ K . E . = mgh }= 10 \times 1 = 10 J\]
Again on the horizontal surface the frictional force,
The block stops after covering 5 m on the rough surface.
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