Answer to Question #224528 in Mechanics | Relativity for Exatelle

Question

An automobile of mass 103kg moves with a velocity of 60m/s. The driver applies the brakes to reduce the velocity to 20m/s. What is the energy dissipated during the application of the brakes?

Answer 1

Solution.

$m=103kg;$

$v_1=60m/s;$

$v_2=20m/s;$

$\Delta W=\dfrac{mv_1^2}{2}-\dfrac{mv_2^2}{2};$

$\Delta W=\dfrac{103\sdot60^2}{2}-\dfrac{103\sdot20^2}{2}=164800J;$

Answer: $\Delta W=164800J.$