Which statement about gravity and mass is true?

• A. Mass does not change with gravity.
• B. Gravity increases mass.
• C. Mass is equal to weight.
• D. Weight is the same as mass.

Answer: (A)

Mass is an intrinsic property of matter that stays the same regardless of where you are. Gravity changes the force with which that mass is pulled, which we call weight. Weight equals mass times gravity (W = m g). So in stronger gravity you weigh more, in weaker gravity you weigh less, but your mass remains unchanged. That’s why the correct statement is that mass does not change with gravity. The idea that gravity increases mass, or that mass equals weight, or that weight is the same as mass, doesn’t fit with how mass and weight relate to gravity. For example, a 50 kg person would weigh about 490 N on Earth but only about 80 N on the Moon, while their mass stays 50 kg.