Year 9 Science · Unit 4 · Lesson 11

Scalars and Vectors; Distance and Displacement

Challenge Worksheet

Name
Date
Class

Learning Goals

Warm Up

Because… chain — GPS, distance, and displacement

Fill in the missing effects. Each step leads to the next in the chain. The first and last steps are given.

A GPS device records your current position using satellite signals
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The GPS calculates the straight-line distance from start to current position
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If the route twists and turns (e.g. running around a lake), the GPS shortcut is shorter than the actual road distance
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A runner's GPS watch can show both displacement (straight-line) and distance (every turn counted)
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Both values are needed in a training session
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Distance tells the runner how much energy they used; displacement tells them which direction they are from the start

Overall outcome:

Go Deeper

Someone claims...

"Speed and velocity are basically the same thing — scientists just use different words to sound more technical. If you know how fast something is moving, you have all the information you need. Just pick whichever term sounds right for the situation."

Evaluate the claim

Construct a rebuttal using 3 specific real-world examples where confusing speed and velocity causes serious errors. For each example: name the context, describe what goes wrong if you only know speed (not velocity), and explain which scientific concept makes velocity the essential quantity.

Example 1. Aviation / aircraft navigation

Challenge2 marks

Example 2. GPS navigation and route calculation

Challenge2 marks

Example 3. Collision avoidance systems (e.g. anti-collision braking in cars or aircraft)

Challenge2 marks

Show What You Know

1. A marathon runner in Sydney completes the 42.2 km City2Surf course. At the finish line in Bondi, they are about 6 km east of the start in Hyde Park. State both the distance and displacement of the runner. Explain which quantity tells their coach how hard they worked, and which tells them where to pick them up.

Challenge 3 marks

Wrap Up

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

HSCScience · Year 9 Science · Unit 4 · Lesson 11 · Challenge Worksheet