1.7.1. Energy
A subsection of Physics, 5054, through 1. Motion, forces and energy
Listing 10 of 76 questions
A man of mass 75 kg falls from a platform high above a lake. a shows the man tied to the platform by a long elastic rope . b shows the man when he has fallen 20 m. After this point the rope begins to stretch. c shows the man at 25 m below the platform where he is first stopped by the rope. 20 m 25 m a b c As the man falls, his gravitational potential energy changes. The gravitational field strength is 10 N / kg. Calculate the change in his gravitational potential energy as he falls through 20 m. change in potential energy = When he is 20 m below the platform, his kinetic energy is equal to the change in his gravitational potential energy calculated in . Calculate his speed at this point. speed = State the energy changes that take place as he falls from 20 m to 25 m below the platform. Ignore the effect of air resistance.
5054_w12_qp_22
THEORY
2012
Paper 2, Variant 2
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Water is transported to a village in a tank pulled by a tractor. shows the tank being pulled by a tractor. water The combined mass of the tractor and the tank is 4100 kg when the tank is empty and 6500 kg when the tank is full of water. The density of water is 1000 kg / m3. Calculate the volume of water in the tank when it is full. volume = At the start of the journey, the tractor and tank accelerate from rest along a straight, horizontal road. As their speed increases, one form of energy is decreasing. State the name of the form of energy that is decreasing. Explain what happens to this energy. The village is located on a mountain at a vertical height of 850 m above the water supply. The gravitational field strength g is 10 N / kg. Calculate the gravitational potential energy gained by the water as it is transported from the supply to the village. energy gained =
5054_w15_qp_22
THEORY
2015
Paper 2, Variant 2
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Questions Discovered
76