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A 1150 kg sports car accelerates from rest to 80 km/h in 7.4s. What is the average power delivered by the engine? Express your answer using two significant figures.

1 Answer

7 votes
First, let's convert the final velocity from km/h to m/s:


image

Next, we'll calculate the acceleration using the formula
image

Now, we can calculate the force using
F=ma, where the mass m = 1150 kg.


F=1150kg×3.0m/s^(2)=
3450N

The next step is to calculate the work done using
image


image

Now, we'll use the formula for power:

image,where
t=7.4s

image

Rounding to two significant figures, the average power delivered by the engine is approximately

image
So, the average power delivered by the engine is around 39 kW.
User CraZyDroiD
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