Question

An object has a kinetic energy at 50 J moving with a speed of 5 m/s.the mad of the object is how many kg?

Answer 1

$ke = \frac{1}{2} m {v}^{2} \\ 50 = \frac{1}{2} m {5}^{2} \\ m = \frac{50 \times 2}{25} \\m = 4kg$