Question

an 800kg race car accelerates uniformly from rest to 15m/s in 3s. solve for work. how much power is delivered by the engine during this time?

Answer 1

The work done is 90kJ, with power delivered 30kJ/s.

Step-by-step explanation:

Work done is proportional to the product of force and displacement. Assuming the motion is in a straight line and the force acts along that line only, the work is calculated as follows:

`W = F\cdot d=(1)/(2)m(at)^2=(1)/(2)mv^2\\W=0.5\cdot 800kg\cdot 15^2(m^2)/(s^2)=90000J`

The work done is 90kJ.

The power is work done per time unit:

`P = (W)/(\Delta t)=(90000J)/(3s)=30kJ/s`

The power delivered in the 3 seconds is 30kJ/s