Physics revision Year 9 Flashcards
Name 11 types of energy
Magnetic, Kinetic, Heat, Light, Gravitational potential, chemical, sound, elastic, electric and nuclear
What measurement do we use for energy?
Joules
Fill in the gaps: As an object falls, its gap energy is turned into gap energy
As an object falls, its gravitational potential energy is turned into kinetic energy
Fill in the gaps: As an object hits an obstacle, it converts its gap energy (as it slows down) into gap energy and gap energy (which dissipate into the surroundings
As an object hits an object, it converts its kinetic energy (as it slows down) into heat and sound energy (which dissipate into the surroundings).
Fill the gaps: As a vehicle accelerates, it converts gap energy (in a fuel/battery) into gap energy (in the brakes)
As a vehicle accelerates, it converts chemical energy (in a fuel/battery) into kinetic energy (as it speeds up)
Fill in the gaps: As a vehicle slows down, gap energy is converted into gap energy (in the brakes)
As a vehicle slows down, kinetic energy is turned into heat energy (in the brakes)
Fill in the gaps: As a kettle boils water, it converts gap energy into gap energy.
As a kettle boils water, it converts electrical energy into heat energy.
How do we calculate kinetic energy?
Kinetic energy=0.5x(speed)^2
How do we calculate gravitational potential energy?
Gravitational potential energy=mass x gravitational field strength x height
How do we calculate power?
Power = work done/time
What is the conservation of energy?
Energy in=energy out. Energy can be transferred usefully, stored or dissipated, but it cannot be created or destroyed.
What is another way to say work done?
Energy transferred
Define power
The rate at which energy is transferred (or the rate at which work is done)
What is power measured in?
Watts (W)
How do we reduce unwanted energy transfers?
Lubricants and thermal insulation
