Answer:
320 J
Explanation:
From the question,
KE = 1/2mv².................. Equation 1
Where KE = Kinetic Energy, m = mass of the rock, v = velocity of the rock
Given: m = 40 kg, v = 4m/s
Substitute these values into equation 1
KE = 1/2(40)(4²)
KE = 20×16
KE = 320 J
Hence the kinetic energy of the rock is 320 J
