Question

Q10. Justify giving proper reasoning whether the work done in the
following cases is 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 sliding down an inclined plane. class 11th​

Answer 1

Answer:

1)in the case of man who is lifting bucket force is exserted by man and displacement happens so yes man is doing work (2) in case of gravitation also the force of gravity pulling it towards it an displacement also occur in this so yes work is done by gravity (3) if you walk on ground then you find that you are applying force in forward direction and covers a certain amount of displacement in it so hence we can also say that it is also a work