Physics Homework! As shown in the diagram, a block of mass m , released from res
ID: 2190270 • Letter: P
Question
Physics Homework!
As shown in the diagram, a block of mass m , released from rest at the top of an incline, slides down a length s from a height h down to the ground. The coefficient of kinetic friction between the plank and the barrel is mu k. Derive an expression for the work done by the force of friction on the block, as it slides down a distance s. Derive an expression for the work done by the force of gravity on the block, as it slides down a distance s. Using the Work-Energy theorem, derive an expression for the change in kinetic energy of the block, between the beginning and end of its slide. Remember: your final answer cannot have any variables in it except those given in the problem!Explanation / Answer
frictional force=u*mgcosangle=u*mg(s^2-h^2)^0.5 /s ; a)work done by frictional force=f*s=u*mg(s^2-h^2)^0.5 ; b) work done by gravity=- mgh ; c) according to work energy theorem ..sum of all works is equal to change in kinetic energy ; change in kinetic energy=u*mg(s^2-h^2)^0.5 -mgh