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2 years ago

A car slows down from speed of 72

Physics

1 answer:

Nastasia [14]2 years ago

5 0

Explanation:

Given parameters:

Initial velocity = 72km/hr

Final velocity = 0km/hr

Time taken = 25s

Unknown:

Acceleration = ?

Solution:

To solve this problem, convert km/hr to m/s;

1000m = 1km

3600s = 1hr

72km/hr;

1km/hr = 0.278m/s

72km/hr = 0.278 x 72 = 20.02m/s

Acceleration is the change in velocity divided by the time taken;

Acceleration = $\frac{final velocity - initial velocity }{time}$

Acceleration = $\frac{0 - 20.02}{25}$ = -0.8m/s

The car is actually decelerating at a rate of 0.8m/s

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Brilliant_brown [7]

Answer:

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