Q5. 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.
Answer– We use the muscular force in squeezing the piece of the lemon to extract its juice. The muscular force is exerted on lemon between our fingers. As a result, the shape of the lemon changed.
(b) Taking out paste from a toothpaste tube.
Answer– We use the muscular force to take out the paste from a toothpaste tube. Muscular force is exerted on the toothpaste tube between our fingers. As a result, the shape of the toothpaste tube changed.
(c) A load suspended from a spring while its other end is on a hook fixed to a wall.
Answer– The load exerts a force on the spring and pushes the spring downward. As a result, the spring gets stretched and its shape gets changed.
(d) An athlete making a high jump to clear the bar at a certain height.
Answer– The athlete pushes the ground with his feet and exerts a muscular force on the ground which allows him to jump over the bar at a certain height. As a result, his state of motion gets changed.