# The mass of a boy is 40 kg on earth. What is his weight on Moon in newton when g=1.568 m/s^2?

The mass of a body is the amount of matter contained in the body and hence stays the same unless we put on more matter. Many times, people use mass and weight interchangeably, which is not correct. Weight, unlike mass, is a force and is the force with which Earth...

The mass of a body is the amount of matter contained in the body and hence stays the same unless we put on more matter. Many times, people use mass and weight interchangeably, which is not correct. Weight, unlike mass, is a force and is the force with which Earth (or any other celestial body one is on) attracts the body. According to Newton's second law, the force is calculated as:

F = m x a

where m is the mass of body and a is its acceleration.

For determining weight, a = g, acceleration due to gravity.

On the Moon, g = 1.568 m/s^2. Mass, however, remains the same on both Earth and the Moon.

Thus, the boy's weight on the Moon = m x g = 40 kg x 1.568 m/s^2

= 62.72 N

Thus, the weight of the boy would be 62.72 N on the Moon.

Hope this helps.

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