Question

A man has a mass of 80 kg on Earth.
a. What is the man’s weight on Earth in Newtons?
b. What is the man’s weight on Mars where the acceleration due to gravity is 3.7 m/s2
?
c. What is the man’s mass and weight while on Moon? Explain your answer.

Answer 1

To calculate weight, we use Newton's 2nd Law of Motion, which gives us the formula "Force = mass x acceleration". We would take the mass given, 80 kg, and multiply it times the acceleration of Earth's downward pull on that mass, 9.8 m/s/s.

784 N = 80 kg x 9.8 m/s/s

So the weight on Earth is 784 newtons.

Now the gravitational attraction of the moon is about 1/6 that of the Earth, or about 17%. To calculate the weight on the moon, simply multiply 784 N times .17, or 17% in decimal form:

784 N x .17 = 133.28 N

So the weight of the same 80 kg mass on the moon is 133.28 N.

Hope it helps ☺️