Question

Explain why the mass of an object remains the same both on earth and on the moon,

but the same cannot be said about the weight of an object.

Answer 1

The mass of an object is the amount of matter or ‘stuff’ it contains. An object's mass stays the same wherever it is.

Mass is measured in kilograms, kg.

Weight is a force that acts upon a mass, and is measured in newtons, N.

The weight of an object depends upon its mass and the gravitational field strength.

weight in N = mass in kg × gravitational field strength in N/kg.

That's why the mass of an object remains the same both on Earth and on the Moon, but not the weight, because gravity is lower on the Moon.