Question

Which of the following is not an example of muscular force?
A. An animal pulling a cart.
B. A man pushing a stationary car.
C. An apple falling from a tree.
D. Two girls pushing each other.

Answer 1

Hint: We can solve this question by keeping certain things in mind which are necessary for a force to be a muscular force. Muscular forces are contact forces that means there should be a contact between the object and the thing where force is applied from. If they do not touch each other then it becomes a non-contact force which is definitely not a muscular force.

Complete step-by-step answer:
Muscular power is the power applied utilizing the organs of the body like arms or legs. It is a force that results because of the action of muscles of the object. It is a contact force since there is contact between the surfaces that are the organs of the body and the object on which force is being applied.
An apple falling from a tree is an example of gravitational force. There is no contact between the apple on which the force is being applied and the earth which is applying the force. Hence, it is a non-contact force and this cannot be a muscular force.
An animal pulling a cart, a man pushing a stationary car and two girls pushing each other are examples of muscular force as all them have a contact between the object on which force is being applied and the object applying the force.
Hence, the correct option is option C.

Note: Gravity or gravitational force can be defined as a natural phenomenon by which all things with mass or energy including planets, stars, galaxies, and even light are brought towards one another by forces of attraction. On Earth, this gravity gives weight to physical objects and matter, and the Moon's gravity causes the ocean tides.