State the sign of work done by a force in the following .
work done by friction on a body sliding down an inclined plane .

State the sign of work done by a force in the following . work done by gravitational force on a body sliding down an inclined plane.

Work done by frictional force

Work done by frictional force

The sign of work done by a force on a body is important to understand .State carefully if the following quantities are positive or negative : (a) work done by a man in lifting a bucket out of a well by means of a rope tied to the bucket . (b) work done by gravitational force in the above case , (c ) work done by friction on a body siding down an inclined plane , (d ) workdone by an applied force on a body moving on a rough horizontal plane woth uniform velocity . (d) work done by the resistive force of air on a vibrating pendulum in bringing it to rest .

State the sign of work done by a force in the following . work done by an applied force on a body moving on a rough horizontal plane with uniform velocity .

The sign of work done by a force is important to understant. State carefully if the following quantities are positive or negative. (a) Work done by a man in lifting a bucket out of a well by means of a rope tied to the bucket. (b) Work done by the gravitational force in the above case. (c ) Work done by friction on a body sliding down an inclined plane. (d) Work done by an applied froce on a body moving on a rough horizontal plane with uniform velocity. (e ) Work done by the resistive force of air on a vibrating pendulum in bringing it to rest.