From the following activities listed below state whether or not work is done .Give your reasons also.
1) A kite is flying due to moving air
2) A man is climbing the stairs
3) A ball is thrown upwards in the air

Dear Student, In all the cases work is done. 1) The air does the work in kite in order to keep it flying. 2) Man does the work for going against the gravity. 3) The motion of throwing does the work upon the ball which ultimately gives the height and force to go against gravity. Regards