Question

What is the velocity of an object with a kinetic energy of 800 J and a mass of 12 kg?

Answer 1

$Given:\\E_k=800J\\m=12kg\\\\Find:\\v=?\\\\Solution:\\\\E_k=\frac{mv^2}{2} \;\;\;/\cdot 2\\\\2E_k=mv^2\;\;\;/:m\\\\v^2=\frac{2E_k}{m} \;\;\;/\sqrt{} \\\\v=\sqrt{\frac{2E_k}{m}} \\\\v=\sqrt{\frac{2\cdot 800J}{12kg} } \approx 11,55\frac{m}{s}$