Question
Assertion : Pulling a lawn roller is easier than pushing it.
Reason : Pushing increases the apparent weight and hence the force of friction.
Reason : Pushing increases the apparent weight and hence the force of friction.
✓
Answer
(a) Suppose the roller is pushed as in figure (b). The force $F$ is resolved into two components, horizontal component $F$ which helps the roller to move forward, and the vertical component acting downwards adds to the weight. Thus weight is increased. But in the case of pull [fig (a)] the vertical component is opposite to its weight. Thus weight is reduced. So pulling is easier than pushing the lawn roller.
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