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bija089 [108]
3 years ago
15

How much work must be done in the car to slow it from 100km/h to 50km/h

Physics
1 answer:
Brilliant_brown [7]3 years ago
7 0

Answer:

-96.465m joule

Explanation:

Let m = mass of the car and v1 = initial velocity and v2 = final velocity

Given.

Initial velocity = 100 km/h

final velocity = 50 km/h

What is work done in the car to slow it from 100km/h to 50km/h?

v1=100km/h=27.78m/s

v2=50km/h=13.89m/s

The work done in the car to slow it from v1 to v2.

w=Δk

w=k2-k1

w= \frac{1}{2}m(v2)^{2}- \frac{1}{2}m(v1)^{2}

w=\frac{1}{2} m(v2-v1)^{2}

w=\frac{1}{2}\times m(13.89 -27.78)^{2}

w=\frac{1}{2}\times m(-13.89)^{2}

w=\frac{1}{2}\times m\times (-192.93)

w=-96.465m joule.

Therefore, the work done is -96.465m joule

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