Respuesta :

Answer: 10kg

Explanation:

Given that:

Kinetic energy of puppy = 245J

Velocity of puppy = 7 m/s

mass of puppy = ?

Recall that kinetic energy is the energy possessed by a moving body. It is measured in joules, and depends on the mass and velocity of the moving body

i.e K.E = 1/2 x mass x (velocity)^2

245J = 1/2 x mass x (7 m/s)^2

245 = 0.5 x mass x 49

245 = 24.5 x mass

Mass = 245/24.5

Mass = 10kg

Thus, the mass of the puppy is 10kg