A 1 kg mass has a K.E of approximately 1 joule when its speed is ______?

0.5 m s⁻¹

1.4 m s⁻¹

1.4 m s⁻²

None of these

Given kinetic energy (K.E) = 1 J and mass (m) = 1 kg:

K.E = ½mv²

1 = ½ * 1 * v²

v² = 2

v = √2 ≈ 1.414

The correct answer is 1.4 m s⁻¹.