Question 5

In the following situations identify the agent exerting the force and the object on which it acts. State the effect of the force in each case.

(a) Squeezing a piece of lemon between the fingers to extract its juice.
(b) Taking out paste from a toothpaste tube.
(c) A load suspended from a spring while its other end is on a hook fixed to a wall.
(d) An athlete making a high jump to clear the bar at a certain height.

Answer

In squeezing a piece of lemon, the muscular force is used to extract juice from it. It is an example of contact force. Our muscles apply force on lemon, then due to squeezing its shape got changed.
In taking out paste from the toothpaste tube, we use muscular force here. Hence its shape got changed due to applied muscular force.
Here, push force is applied by the load on the spring. Due to it, spring goes downward. Hence, the spring is stretched and the shape of the spring is change due to the applied push force.
Here, athlete applies push force on the ground with his feet. By doing this, his muscular feet feels some muscular force on the ground. Due to this, he jumps over the bar. Change in the motion of the athlete occurs by applying push and muscular force.

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