Question
(a) Define work.
(b) What are the conditions for doing work?
(c) State the mathematical expression for work.
(b) What are the conditions for doing work?
(c) State the mathematical expression for work.
✓
Answer
(a) Work is said to be done only when the force applied on a body causes a displacement of the body in the direction of force or any resolved component of the force.
(b) Conditions for doing work:
(i) There must be a force acting on the body.
(ii) The force acting on the body must cause a displacement.
(iii) The displacement must be in the direction of force or its resolved component.
(c) Mathematically, work is the product of force and the displacement in the direction of force.
$W =\overrightarrow{ F } \overrightarrow{ S }= FS \cos \theta$ (if force acts at angle $\theta$ with horizontal)
(b) Conditions for doing work:
(i) There must be a force acting on the body.
(ii) The force acting on the body must cause a displacement.
(iii) The displacement must be in the direction of force or its resolved component.
(c) Mathematically, work is the product of force and the displacement in the direction of force.
$W =\overrightarrow{ F } \overrightarrow{ S }= FS \cos \theta$ (if force acts at angle $\theta$ with horizontal)
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