State the law of conservation of energy.
The law of conservation of energy states that energy can neither be created nor destroyed, it can only be transformed from one form to another.
Which law was verified experimentally by James Prescott Joule?
Law of conservation of energy
What is the amount of work done by a man in pressing a rigid wall with a force of 400 N?
Zero because there is no displacement.
A coolie is walking on a railway platform with a load of 27 kg on his head. What is the amount of work done by him?
Work done by the coolie is zero, as W = Fs cos 90° = 0.
Moment of force and work done by a force have the same units. Then, what is the difference between them?
The moment of force (also called torque) and work done by a force both have the same unit, which is the Newton-meter (Nm). However, they represent different concepts. Moment of…
From where do we get energy for the life processes?
The energy required for the various life processes comes from the food that we eat.
Explain the following terms with one example each: (a) Positive work (b) Zero work
(a) When force acts in the direction of motion of body work done is positive. When a lawn roller is pulled forward, work done is positive. (b) When force is…
List two conditions which need to be satisfied for the work to be done on an object.
W = Fs Work is done when (a) a force acts on an object (b) object is displaced.