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3 years ago

15

Help me plz.Show workings

2 answers:

Ksenya-84 [330]3 years ago

8 0

This question is a good example of the difference between 'speed' and 'velocity'. This one is all 'velocity', and you've absolutely gotta keep the directions straight.

The object started out moving forward at 10 m/s. It ended up moving backward at 2 m/s. What was the change in its velocity ?

The change was <u>12 m/s backward</u> !

Momentum = (mass) x (velocity).

Change in momentum = (mass) x (change in velocity)

This change in momentum = (0.1 kg) x (12 m/s backward)

This change in momentum = 1.2 m/s backward or <em>1.2 Ns (B)</em>

ddd [48]3 years ago

3 0

Change in momentum: finial momentum - initial momentum
Momentum = mass * velocity
Mass = 100g, same as 0.1kg
m(v-u) = 0.1(10-2) = 0.1(8)
The answer is 0.8Ns

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