A 1300 sports car accelerates from rest to 90 in 6.5 .
What is the average power delivered by the engine?
power=rate of KE change= 1/2 *1300*90^2/6.5 assuming the units are right, you didn't indiate them.
To calculate the average power delivered by the engine, we need to use the equation:
Power = Work / Time
First, we need to calculate the work done by the engine. The work done can be calculated using the formula:
Work = (1/2) * mass * velocity^2
Given that the car accelerated from rest (initial velocity = 0) to a final velocity of 90 m/s, we can substitute the values into the formula:
Work = (1/2) * mass * (90^2)
However, we are not given the mass of the car. So, we cannot calculate the work done directly.
But we can use the fact that power is the rate at which work is done. Since we know the time taken for the acceleration, we can use the relationship:
Power = Work / Time
In this case, the work done is the change in kinetic energy as the car accelerates, which can be calculated using the equation:
Work = (1/2) * mass * (final velocity^2 - initial velocity^2)
Since the car starts from rest, the initial velocity is 0. So, the equation reduces to:
Work = (1/2) * mass * (90^2 - 0^2)
The time taken for the acceleration is given as 6.5 seconds.
Now, substitute the calculated work and the given time into the equation:
Power = Work / Time
Power = [(1/2) * mass * (90^2)] / 6.5
The average power delivered by the engine can be determined by solving this equation. Keep in mind that we need the mass of the car to calculate the actual value of the power.