Answer:
K.E. increase by 10 KJ.
Explanation:
Total mechanical energy of a system is always constant which is the sum of kinetic and potential energies of the system. So, when the ram of a pile driver when it suddenly undergoes a 10 kJ decrease in potential energy, its kinetic energy must have increase by 10 KJ. So, as to make their sum constant again.
Mechanical energy = Kinetic energy + potential energy = constant
