Energy stores and transfers
What are 3 Energy stores
3 energy stores
What is the equation for GPE
GPE= m x g x h
Define renewable
Can be used up at the same rate at which it can be replaced
State the work done equation
WD= F x D
Calculate the pressure if a dart exerts 30N of force over an area of 0.05m.
64 N/m^2
What are the 4 energy transfers
mechanically, electrically, heating and radiation
What is the equation with units to calculate KE?
KE = 1/2m x V^2
Name 3 renewable energy resources
correct responce
Define power
The rate of energy transfer
Describe factors that affect gas pressure
temp, volume
What is the law of conservation of energy
Energy can not be created or destroyed only transferred
Calculate the GPE if the a box with a mass of 10Kg is raised 10m
1000 J
Describe how hydroelectric power can be produced
Water has GPE, when it falls in gains KE, this KE can turn a turbine, which can turn a generator, and convert KE into electrical energy
Define Work
The energy transfered
Explain why pressure increases with depth in water
more particles on top = more pressure
Draw the energy stores and transfers for someone firing a sling shot - start with the energy stored in thier muscles
Chemical -> elastic potential -> Kinetic -> heat/sound
Calculate the Velcoity of a car that has a mass of 500kg and is travelling with 20,000J of energy.
8.94 m/s
Describe and explain the main problem with fossil fuels
Carbon dioxide - contributes to global warming
Non- renewable - will eventually run out
Why might a calculated value for energy required to do a task not be the same as the actual value for the work done?
Explain why people may lie down to move oevr ice rather than walk
Draw the energy stores and transfers for lighting a match. Start at the energy stored in the match.
Chemical -> Kinetic -> Thermal -> Sound
If a sky diver has 2000J of GPE at the beginning of a sky dive, how much KE do they have when they have fallen 3/4 of the way to the ground? What assumptions have you made?
1500J
No energy is lost to air resistance
What is the original source of energy for solar, fossil fuels, wind, and hydroelectric and wave energy?
The sun
Two people do the same amount of work with the same force. Why does one person require more power?
They are doing the work faster
If water has a mass of 10000kg and occupies a volume of 10m^3, how much pressure would you experience at 2.5m deep?
250000 pa