Question

If a 1600-kg vehicle travels at 10 m/s (or approximately 22 mph), then find its kinetic energy in kilojoules (kj).

Answer 1

The kinetic energy of a moving body is given by,

$K =\frac{1}{2} m v^2$

Here, m is mass of the body, v is its velocity.

Given,   m= 1600-kg and v = 10 m/s.

Substituting these values in above equation, we get

$K = \frac{1}{2} (1600 \ kg ) (10 \ m/s)^2 = 80000 \ J$

In kilojoules,

$K = 80000 \ J = 80 \times 10^3 \ J = 80 \ kJ$

Thus, the kinetic energy of vehicle is $80 \ kJ$