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2 years ago

5

To drive your car from Auburn to Atlanta (173.8 km) takes a significant amount of work. Assuming the force of friction between t

he tires and the road is 10290 N, how much work needed to drive that far? Express your answer in megajoules (MJ).

1 answer:

Daniel [21]2 years ago

5 0

Answer:

1788.402 MJ

Explanation:

Work done = Force (N) x distance (m)

First we have to convert distance into metres:

173.8 x 1000 = 173,800 m

Then plug these values into the equation above:

173,800 x 10290 = 1788402000 J

The reason it's Joules (the unit for energy) is because work done = energy transferred

Now we have to convert Joules into Mega Joules:

1 J = 1/1000000 MJ

1788402000 J = 1788402000/ 1000000 = 1788.402 MJ

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Solving for $\omega_f$ , we find the final angular speed after 10.0 s:

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If we re-arrange it for t, we get:

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where here we have

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$t=\frac{0-2000 rad/s}{-80.0 rad/s^2}=25 s$

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Momentum = (mv).
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