Answer to Question #243891 in Physics for Kanth

Question

Whats the kinetic energy of a car that's mass is m=1000kg that is traveling at a speed of 100km per hour

Answer 1

By definition, the kinetic energy is:

$$K = \dfrac{mv^2}{2}$$

where $v = 100km/h = 100/3.6\space m/s$ is the speed of the car, and $m = 1000kg$ is its mass. Thus, obtain:

$$K = \dfrac{1000\cdot (100/3.6)^2}{2} \approx 3.86\times 10^5J$$

Answer. $3.86\times 10^5J$.