A vessel contains water. Paddles that are
propelled by falling masses turn in the wa-
ter, causing the water’s internal energy to in-
crease. The temperature of the water is then
measured, giving an indication of the water’s
internal energy increase.
If a total mass of 14.5 kg falls 5.39 m and
all of the mechanical energy is converted to
internal energy, by how much will the internal
energy of the water increase? The accelera-
tion of gravity is 9.81m/s2 . Assume no energy
is transferred as heat out of the vessel to the
surroundings or from the surroundings to the
vessel’s interior.
Answer in units of J


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