The kinetic energy (K.E.) of a body can be calculated using the formula:
K.E. = (1/2) * m * v^2
Where: K.E. is the kinetic energy m is the mass of the body v is the velocity of the body
Plugging in the values given: m = 12 kg v = 400 m/s
K.E. = (1/2) * 12 kg * (400 m/s)^2 K.E. = (1/2) * 12 kg * 160,000 m^2/s^2 K.E. = 6 kg * 160,000 m^2/s^2 K.E. = 960,000 m^2/s^2
Therefore, the kinetic energy of a body with a mass of 12 kg and moving with a velocity of 400 m/s is 960,000 joules (J).