Work Energy Power Question
1. An apartment block receives water from a nearby reservoir. A pump is necessary to lift the water into a storage tank at the top of the building. How much extra energy must the pump supply to each one kilogram of water, in order to lift it into the tank? (gravitational field strength is 10 N/kg)
There are two ways to analyze this question:
2. The diagram below shows a boy of 65.0kg using a ‘chin-up’ bar to lift himself up.
3. A falling metal hammer is used to drive a hollow steel post into the ground as shown in the Figure below. The hammer is lifted by an electric motor and it then falls freely to hit the baseplate.
(a) As the hammer falls, the gravitational potential energy is converted to kinetic energy.
4. The Figure below shows a roller coaster with a mass of 900 kg coasting on a track. When it reaches point A, it is moving at 5 m/s. Assume there is no friction and air resistance.
(a)(i) KE = 0.5mv2