A) friction will be 960 J
B) friction will be - 960 J
C) man will be 960 J
D) man will be-960 J
Correct Answer: C
Solution :
By work K.E. theorem Work done by all the forces external and internal equals to change in KE \[{{W}_{f}}+{{W}_{man}}\,+{{W}_{N}}+\,{{W}_{g}}\,=\Delta KE\,=960J\] \[{{W}_{f}}=0\] Because displacement of point of application of friction will be zero during the movement of the man. \[{{W}_{N}}=0,\,{{W}_{g}}=0\] Because N and mg acting perpendicular to the displacement. Hence work done by man is 960 J.
You need to login to perform this action.
You will be redirected in
3 sec
