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28 Cards in this Set
- Front
- Back
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what is the equation for gravitational potential energy? Give SI units for all quantities involved. |
Mass times gravitational field strength times. Change in high energy in joules, mass in kilograms, gravitational field strength in newtons to kilograms in height In metres |
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what is the equation for kinetic energy give us our unit for all quantities involved |
Half mass times velocity, squared energy in joules, mass in kilograms velocity in metres. Squared |
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What is meant by the conservation of mass? |
The total amount of energy in a close system remains constant. Energy cannot be made or destroyed, but can change from one form to another. |
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describe the energy changes involve a ball is thrown upwards and then returned into it starting position. Ignore Iris assistance |
And upwards kinetic energy is converted into gravitational potential energy. At the peak, there is a maximum gravitational, potential energy in zero kinetic energy. Downwards, the gravitational potential energy is converted into kinetic energy |
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how is kinetic energy related to the mass of the moving object? |
It’s directly proportional |
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name the four energy transfers and what they do |
Mechanically force moving through a distance. Electrically electric current? Radiation, electro, electromagnetic and sound waves. thermic difference in temperature |
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name the energy stores and give examples |
Gravitational potential electrostatic elastic Kinetic Sound Magnetic Chemical Thermal Nuclear
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Describe the energy transfers for a bungee jumper |
When falling the gravitational potential energy is converted to kinetic energy of the jumper. As a cold, Titans kinetic energy is converted installed is elastic potential energy. At the lowest point the jumpers national Grace gravitational potential energy equals the elastic potential energy stored in the cord. |
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Explain why a bungee jumpers slows down want to call begin to stretch |
Kinetic energy decreases since it is converted into elastic potential energy. Since kinetic energy is proportional to velocity, squared as kinetic energy decreases, so does it Velocity |
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What is waste energy? |
The energy that is not used by the device device device for a desired purpose or not converted to it desired form |
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State to state two equations to calculate efficiency |
Useful Energy used by device divided by, total energy
or Useful power, output divided by, total power output |
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Explain what a closed system is |
A system has no external forces acting on it. The total energy in the system never changes and no energy is lost, and Of mass no transfer of mass |
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explain what an open system |
Energy can be transferred out of the system and therefore the total energy of the system can change. Moss can be transferred |
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in mechanical processes, what can happen to the energy that gets transferred? |
Energy transferred can cause a rising temperature. Energy can be dissipated to the surroundings. Causing a wasteful process |
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State the consequence for energy transfer of a material with a high thermal conductivity |
The rate of energy transferred through the material is higher for a material with a lower thermal conductivity |
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State three methods of reducing heat loss in a building |
Carpets? Wall cavities. Double glazing Double glazing. |
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how do you reduce unwonted energy transfer in a mechanical system? |
Lubrication and thermal insulation |
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How can the efficiency of a system be increased? |
Reducing weight output. Recycling waste output |
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What’s the efficiency equation ratio? |
Efficiency equals useful energy transferred by the device divided by total energy supplied to do to the device |
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name the energy sources for household use |
Fossil fuse Nuclear fuel? Biofuel. Wind Hydro electricity. Tidal Solar |
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State two patterns and trends in the use of energy resources |
During industrial revolution, fossil feels became an important source of energy as it was easy to mine Renewable energy sources have only become suitable recently has technology has had to develop. Population growth means that finite resources are getting you so much quicker and new ways of energy. Needed to be found |
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What happens when an object is projected upwards |
Kinetic energy transferred into gravitational potential energy than the opposite when it falls back down |
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what happens when an object is projected of a slope |
Kinetic energy transferred to a gravitational potential energy, and possibly to heat. Friction is present. |
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What is the energy change when a moving object hits an obstacle? |
Kinetic energy is transferred to sound or kinetic energy is transferred to the object of the object move to. Object be |
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I need to change when objects being accelerated by a constant force |
Whatever object with having work done to it, it’s gain in Connecticut energy. Whatever supplies the force is having its energy transferred to kinetic energy |
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What is the energy change when a vehicle is slowing down? |
Kinetic energy is transferred to heat through the brakes |
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what is the energy change from boiling water in a kettle? |
electrical energy is changed thermal |
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What’s a type of diagram you can show energy transferred |
Sankey diagrams or flow diagrams |
