A diver with a mass of 51 kg reaches a maximum height of 5.8 m above the water. When the diver has fallen 2.8 m from the apex, what is her kinetic energy (J)? Assume horizontal velocity is zero.

just figure how much potential energy (mg ∆h) has been lost. That has been converted to kinetic energy.

P.E=mgh m=51kg g=9.8ms^2 h=2.8m 51*9.8*2.8=1399.44j

To find the kinetic energy, we first need to calculate the potential energy of the diver at the apex and then calculate the potential energy of the diver at 2.8 m below the apex. The difference between these potential energies will give us the kinetic energy.

1. Calculate the potential energy at the apex:
Potential Energy (PE) = mass x gravitational acceleration x height
PE_apex = 51 kg x 9.8 m/s^2 x 5.8 m

2. Calculate the potential energy at 2.8 m below the apex:
PE_below_apex = mass x gravitational acceleration x height
PE_below_apex = 51 kg x 9.8 m/s^2 x (5.8 m - 2.8 m)

3. Calculate the difference in potential energy:
ΔPE = PE_apex - PE_below_apex

4. Convert the difference in potential energy to kinetic energy:
Kinetic Energy (KE) = ΔPE

By following these steps, you can calculate the kinetic energy of the diver.