Question

In Column I some statements are given related to work done by a force on an object while in Column II the sign and information about value of work done is given. Match the entries in Column I with the entries in Column II.

Answer 1

(A) Since block slides downwards and friction force acts upwards therefore, Work done by friction is negative.
A- >2
(B) Since incline does not move therefore, work done is zero.
B- >3
(C) Since man does work against gravity and bucket is lifted up. Force applied by man and displacement of bucket are in same direction, hence, work done is positive.
C- >1
(D) Total work done by friction$=$ work done by friction on block $+$ work done by friction on incline $=$ negative $+$ zero$=$negative.
Therefore,
D- >2