What is the speed of a 48 kg dog running across a lawn with 216 J of energy?

The speed of dog is 3 m/s!

Explanation:

The mass m of the dog is given as 48 kilograms

And Kinetic energy as 216 joules

As we know K. E = (1/2) mv^2

216 = (1/2) * 48 * v^2

216 = 24 * v^2

v^2 = 216 / 24

v^2 = 9

v = 3 m/s