Question

‘The action and reaction are equal in magnitude.’ Is this statement true, and which law is related to it?
A.Yes, Newton’s second law
B.Yes, Newton’s third law
C.No, Newton’s third law
D.Yes, Newton’s first law

Answer 1

From the third law of Newton, we can know, every action in nature has an equal and opposite reaction. So, obviously, the action and the reaction are equal in magnitude. This implies that the given statement must be true.

Complete step by step answer:
Newton’s third law states that, to every action, there is always an equal and opposite reaction. Alternatively, the mutual actions of any two bodies A and B are always equal in magnitude and opposite, being directed along the same straight line.
So, the given statement in the question is true and is related to the third law of Newton.
Therefore, the correct option is (B) Yes, Newton’s third law.

Additional information:
The study of particle dynamics can be best made on the basis of Newton’s laws, which are ingenious generalizations based on observations and are thus empirical laws. These laws deal with the motion of macroscopic bodies with velocities much smaller than the speed of light.
The first law of Newton says that each body continues to be in its state of rest or uniform motion in a straight line unless acted upon by some external force(s).
The second law of Newton can be stated as the (time) rate of change of linear momentum of a particle or body is proportional to the external impressed force and takes place in the direction of the force.
And the third law is stated earlier. This law applies to two isolated bodies that interact mutually by exerting forces on each other. Forces, due to all other bodies, are then absent.

Note:
By the third law, the force on the particle $1$ due to particle $2$, i.e., ${{\vec{F}}_{12}}$ is equal and opposite to that on $2$ due to $1$ , i.e., ${{\vec{F}}_{21}}$ . Therefore, ${{\vec{F}}_{12}}=-{{\vec{F}}_{21}}$ . The third law is thus a law of reciprocity. It means that action and reaction are equal and opposite and act on opposite bodies.