Year 7 Science · Unit 3 · Lesson 2

Gravity and Weight vs Mass

Apply Worksheet

Name
Date
Class

Learning Goals

Read the graph

The bar chart below shows the weight of a 70 kg astronaut on four different bodies in the Solar System. Study the graph, then answer the questions.

Weight of a 70 kg person on four Solar System bodies 0 500 1000 1500 Weight (N) 686 N Earth 112 N Moon 259 N Mars 1736 N Jupiter Weight of a 70 kg astronaut across the Solar System

Data: calculated using g values from the lesson (Earth 9.8, Moon 1.6, Mars 3.7, Jupiter 24.8 N/kg).

(a) On which body does the astronaut weigh the most? Approximately how many times heavier is this compared to their weight on Earth?

Apply 2 marks

(b) The Moon's g = 1.6 N/kg. Use W = m × g to verify the 112 N figure shown for the Moon. Show your working.

Apply 2 marks

(c) The astronaut's mass is 70 kg on Earth. What is their mass on Jupiter? Explain your reasoning.

Apply 2 marks

Compare two

Complete the table to compare mass and weight. Fill in both cells for each feature.

FeatureMassWeight
Unit of measurement
Does it change on the Moon?
What instrument measures it?
Is it a force?
Formula (if any)

1. A student says: "An astronaut in the ISS is weightless — there's no gravity up there." Identify two errors in this statement and write the correct scientific explanation.

Apply 3 marks

2. A 50 kg student travels to Venus (g = 8.9 N/kg). Calculate their weight on Venus using W = m × g. Show your working. Then explain whether their mass has changed compared to on Earth, and why.

Apply 3 marks

Wrap Up

In one sentence, what was the main idea of this lesson?