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Unit summary

Check your knowledge and understanding

1. Look at the graph below. It maps out how the 2. A car is moving at a speed of 90 km/h and a
distances covered by 3 different people change truck is moving at a speed of 54 km/h. Calculate
with time. Explain, in detail, how they compare. the relative speed of the two vehicles when
textbooks nis edu kz
Use the vocabulary learnt in this unit. Calculate they move:
the speed of each person and plot a speed vs. a) in the same direction
time graph that contains all 3 people. Compare
the graphs. b) towards each other
3. The same car and truck are now travelling west
d (metres) on the Almaty–Astana motorway. The car is
cyclist runner
25
45 km along the motorway, and the truck 70 km.
At what point will the car overtake the truck?
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What assumptions do you need to make to solve
15 this problem?

4. A motorboat covers 30 km in 2.5 hours when it
10 walker
moves with the flow. How much time will it need
5 for the return journey if it is going at a speed of
4 km/h?
t (seconds)
2 4 6 8

Assess your learning

Reflect on how well you met the learning objectives of this unit. Use the worksheet provided by
your teachers to develop your own targets.

How confident am I?

I can …
explain the physical meaning of the following terms: trajectory, distance, displacement, speed
calculate speed and express its magnitude using SI measurement units

explain when an object is at rest and when it moves uniformly
calculate speed using a displacement vs. time uniform motion graph

describe group vector and scalar quantities and give examples
solve problems on relative motion

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