Which of these objects would have greater mass, object A that weighs 50N on earth or object B with a weight of 50N on the moon?

2 Answers
Jul 28, 2017

Object B (The object on the Moon)

Explanation:

We're asked to find which of two objects has a greater mass, given that they have the same weight on two different celestial bodies.

Recall Newton's second law, which states

sumvecF = mvecaF=ma

We need to know the magnitude of the acceleration gg for each body. We know earth's is 9.819.81 "m/s"^2m/s2, and the Moon's is 1.6241.624 "m/s"^2m/s2 (from Internet or any resource).

Earth:

We have

  • sumF = 50F=50 "N"N (weight)

  • a = 9.81a=9.81 "m/s"^2m/s2

Thus,

m = (sumF)/a = color(red)(5.10m=Fa=5.10 color(red)("g"g

Moon:

We have

  • sumF = 50F=50 "N"N (weight)

  • a = 1.624a=1.624 "m/s"^2m/s2

So

m = (sumF)/a = color(blue)(30.8m=Fa=30.8 color(blue)("g"g

Thus, object sfcolor(blue)("B" has the greater mass.

Jul 29, 2017

B

Explanation:

Intuitively, since gravity on the moon is less than that on Earth, it takes more mass on the moon to produce the same force.