Determine the kinetic energy of a body weighing 2 kg moving at a speed of 72 km / h.

To determine the kinetic energy of a body with a mass of m = 2 kg, moving at a speed of v = 72 km / h, we first translate the value of the speed into the SI system: v = 72 km / h = 72 ∙ 1000 m / 3600 s = 20 m / s , then we will use the formula for calculating the kinetic energy: E (kin) = (m ∙ v ^ 2): 2. Substitute the values of physical quantities into the formula and perform calculations: E (kin) = (2 kg ∙ (20 m / s) ^ 2 ): 2; E (kin) = 400 J.
Answer: the kinetic energy of the body is E (kin) = 400 J.