# At what speed should a person weighing 80 kg run so that his kinetic energy is equal to a kinetic bullet

At what speed should a person weighing 80 kg run so that his kinetic energy is equal to a kinetic bullet of 9 grams flying at a speed of 600 m / s

Initial data: mh (mass of a running person) = 80 kg; mp (bullet weight) = 9 g (9 * 10 ^ -3 kg); Vp (bullet speed) = 600 m / s.

The speed at which a person should run is determined from the equality: Ek1 = 0.5 * mh * Vch ^ 2 = 0.5 * mp * Vp ^ 2 = Ek ^ 2, whence Vch ^ 2 = mp * Vp ^ 2 / mh and Vh = √ (mp * Vp ^ 2 / mh).

Calculation: Vh = √ (9 * 10 ^ -3 * 600 ^ 2/80) = √40.5 = 6.36 m / s.

Answer: A person must run at a speed of 6.36 m / s. One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.