A 850-kg sports car accelerates from rest to 95 km/h in 5.0 s

Question

A 850-kgkg sports car accelerates from rest to 95 km/hkm/h in 5.0 ss . What is the average power delivered by the engine?

Express your answer to two significant figures and include the appropriate units.

Answer 1

Power is equal to Work/time. We know that the engines running for 5 seconds so t=5s

Now we just need the Work done by the engine.

Work = Force • distance.

To get the force of the engine, we know it's moving a 850kg sports car.

Change the 95km/h into units of m/s

Then to get the acceleration, divide that by the 5 seconds it took to accelerate.

Force is equal to mass * acceleration so multiply the mass of the car by this acceleration

To get the distance, we have to use kinematics.

We know the acceleration, the time, and the initial velocity (0m/s)

Use the equation: x = 0.5at²+v₀t to get the distance.

Solve for the work and then get the power by dividing the work by 5 seconds