Page 83 - York Global Science 6 - Physical Science

Physical Science

70 km/h + 50 km/h = 120 km/h
The relative speed of the cars is 120 km/h.

The person standing on the side of the road still uses the Earth as a frame
of reference. To this person, the speed of each car looks the same in both
situations.

Let’s Understand

Look at this picture.

100 km/h

60 km/h

1 How fast is the car moving?
2 How fast is the train moving?

3 What is the relative speed of the train to the car?

4 Explain why the relative speed is different to the real speeds.

Now answer the questions in the Workbook

Let’s Reflect

1 How can you find the relative speed of objects moving in opposite
directions?

2 Give an example.

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