1.7.3. Energy resources
A subsection of Physics, 0625, through 1. Motion, forces and energy
Listing 10 of 215 questions
shows a simplified version of a ‘gravity lamp’. This apparatus is used to light a light-emitting diode (LED) without mains electricity. LED attachment to ceiling generator strap 12 kg load The load of 12 kg is raised to a height of 1.7 m above the ground. The load is connected to a pulley system. The time taken for the load to fall to the ground is 1200 seconds. The load falls at constant speed. The generator is connected to an LED. Calculate the rate of transfer of gravitational potential energy as the load falls to the ground. rate of transfer of gravitational potential energy = The light output of the LED is 0.10 W. Calculate the efficiency of the ‘gravity lamp’. efficiency = Suggest a social or environmental advantage of using a ‘gravity lamp’.
0625_w21_qp_43
THEORY
2021
Paper 4, Variant 3
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State the principle of conservation of energy. shows the energy flow diagram for a car powered by a petrol engine. chemical energy store 100% kinetic energy store internal energy store and sound 70% Using the information in , calculate the percentage of energy transferred from the chemical store to the kinetic store. percentage = % shows the energy flow diagram for an electric car. The electric car is driven by an electric motor which is powered by a battery. kinetic energy store 70% internal energy store 30% chemical energy store 100% Using the information in and , state which car is more efficient. Give a reason for your answer. car reason
0625_w23_qp_32
THEORY
2023
Paper 3, Variant 2
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Questions Discovered
215