Question

22) A driver traveling at 80 km/h brakes her 2000 kg truck to stop for a red light. How much internal energy is produced

Answer 1

Answer:

$E=4.9\times 10^5\ J$

Explanation:

Given that,

The speed of a driver, v = 80 km/h = 22.22 m/s

The mass of the truck, m = 2000 kg

We need to find how much internal energy is produced. The internal energy produced by a truck is its kinetic energy and it is given by :

$E=\dfrac{1}{2}mv^2\\\\E=\dfrac{1}{2}\cdot22.22^{2}\cdot2000\\\\E=493728.4\ J$

or

$E=4.9\times 10^5\ J$

So, $4.9\times 10^5\ J$ of internal energy is produced.