10 ??
A small block of mass m is kept on a rough inclined surface of inclination θ fixed in an elevator. The elevator goes up with the uniform velocity v and the block does not slide on the wedge. The work done by the force of friction on the block in time t will be how much.
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2 Answers
62No the work is not zero...
We had solved this question sometime back on this forum
Well the solution is this way
Work done is f.ds
ds is not zero (see the ground frame!)
The direction of friction is along the slope.
But the displacement is in the upwards direction.
Total displacement is v.t
frictional force is F (this has to be calculated! cos you have not given anything.. And bcos it is static friction so this can also not be equated to μN) But the point of this question is something else altogether!!
Friction will be at angle theta!!
so take the dot product of F and displacement.