Question

3. Imagine a 10kg block moving with a speed of 20m/s calculate the kinetic energy of this block

Answer 1

The formula of the kinetic energy is:
$E_{k} = \frac{m v^{2} }{2}$
where m is a mass of the object, v is speed of the object at the moment of time. So we have:
$E_{k} = \frac{10* 20^{2} }{2} = 2000J$
The answer is 2000 Joules.