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3 years ago

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As part of a safety investigation, two 1900 kg cars traveling at 20 m/s are crashed into different barriers. Part A Find the ave

rage force exerted on the car that hits a line of water barrels and takes 1.3 s to stop.

1 answer:

DedPeter [7]3 years ago

8 0

Answer:

- $29.2\times 10^{3} N$

Explanation:

We are given that

Mass of cars= m=1900 kg

Initial speed of car=u=20 m/s

Final speed of car=v=0

Time= $\Delta t$ =1.3 s

We have to find the average force exerted on the car.

Average force= $\frac{change\;in\;momentum}{\Delta t}$

$F_{avg}=\frac{mv-mu}{1.3}$

$F_{avg}=\frac{1900(0)-1900(20)}{1.3}$

$F_{avg}=\frac{-38000}{1.3}=-29.2\times 10^{3} N$

Hence, the average force exerted on the car that hits a line of water barrels=- $29.2\times 10^{3} N$

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Answer:

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