Question

State carefully whether the following work done is positive, negative or zero:
a. Work done by a boy for lifting a suitcase.
b. Work done by gravitational force in lifting a suitcase.
c. Work done by friction on a body which is sliding along a surface
d. Work done by an applied force on a body which is moving on a rough horizontal surface with uniform velocity.
e. Work done by the resistive force of air on a vibrating body to bring it to rest.

Answer 1

Answer:

positive

negative

negative

positive

ne