Question

stations review 12/3/25
station #1: mass vs. weight (5 min)
problem: an astronaut has a mass of 80 kg.
weight on earth (g = 9.8 m/s²):
weight on moon (g = 1.6 m/s²):
explain in one sentence why mass doesn’t change but weight does.
prepare to teach the class: the difference between mass and weight.

Explanation:

Step1: Calculate Earth weight

Weight formula: $W = m \times g$. Substitute $m=80\ \text{kg}$, $g=9.8\ \text{m/s}^2$:
$W_{\text{Earth}} = 80 \times 9.8 = 784\ \text{N}$

Step2: Calculate Moon weight

Use same formula, substitute $g=1.6\ \text{m/s}^2$:
$W_{\text{Moon}} = 80 \times 1.6 = 128\ \text{N}$

Step3: Explain mass vs weight difference

Mass is constant matter amount; weight depends on gravity.

Mass is the amount of matter (constant), while weight is gravitational force (varies with gravity).

Answer:

Weight on Earth: 784 N
Weight on Moon: 128 N