Activity _____________ `11.1`
♦ We have discussed in the above paragraphs a number of activities which we normally consider to be work in day-to-day life. For each of these activities, ask the following questions and answer them:
i) What is the work being done on?
(ii) What is happening to the object?
(iii) Who (what) is doing the work?
♦ Think of some situations from your daily life involving work
♦ List them.
♦ Discuss with your friends whether work is being done in each situation.
♦ Try to reason out your response.
♦ If work is done, which is the force acting on the object?
♦ What is the object on which the work is done?
♦ What happens to the object on which work is done?
♦ Think of situations when the object is not displaced in spite of a force acting on it.
♦ Also think of situations when an object gets displaced in the absence of a force acting on it.
♦ List all the situations that you can think of for each
♦ Discuss with your friends whether work is done in these situations.
♦ Lift an object up. Work is done by the force exerted by you on the object. The object moves upwards. The force you exerted is in the direction of displacement. However, there is the force of gravity acting on the object.
♦ Which one of these forces is doing positive work?
♦ Which one is doing negative work?
♦ Give reasons.