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Question
Figure shows a boy pulling a wagon on a road. List as many forces as you can which are relevant with this figure. Find the pairs of forces connected by Newton's third law of motion.

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Solution
List of forces :
(a) A pair of gravitational force between the wagon and the Earth.
(b) A frictional force exerted by the road on the wagon.
(c) A tension exerts electromagnetic force between the wagon and string.
(d) A pair of gravitational force between the man and the Earth.
(e) A frictional force exerted by the road on the man.
(f) A tension exerts electromagnetic force between the man and string.
Here, (a), (c), (d) and (f) are pairs of forces associated with Newton's third law of motion.
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