Year 7 Science · Unit 3 · Lesson 5

Newton's First Law — Inertia

Foundation Worksheet

Name
Date
Class

Learning Goals

Match each term to its definition

Draw a line connecting each term on the left to its correct definition on the right. Or write the matching letter next to each term.

TermYour answerDefinition
Newton's First LawA. A non-zero net force that causes a change in motion
InertiaB. Moving at the same speed in the same direction — no change in motion
Balanced forcesC. The tendency of an object to resist any change in its motion
Unbalanced forcesD. When forces cancel out and net force = zero
Net forceE. Objects stay at rest or at constant velocity unless an unbalanced force acts
Constant velocityF. The total force after all individual forces are added with direction

Odd one out

Circle the item that does not belong in each group. Then explain why it doesn't fit.

#GroupYour answer (odd one + reason)
1 Seatbelt    Headrest    Airbag    Speedometer
2 Voyager spacecraft coasting    Cricket ball in flight    Car engine off    Rocket at full thrust
3 68-tonne B-train truck    Fully loaded shopping trolley    Empty bicycle    Sumo wrestler

1. A ball is rolling across a smooth floor and gradually slows down. A student says "the ball slows down because it has run out of force." Use Newton's First Law to explain what is ACTUALLY happening.

Recall 2 marks

2. A B-train truck has about 45 times more mass than a family sedan. Use the concept of inertia to explain why the truck needs a much longer stopping distance.

Recall 2 marks

Wrap Up

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