P1.6 - Energy, Work, Power & Pressure Flashcards
What are ways energy can be stored? [7]
- kinetic
- gravitational potential
- chemical
- elastic
- nuclear
- electrostatic
- thermal
What is energy? [1]
the ability of a body to perform work
What is the principle of conservation of energy? [2]
energy cannot be created or destroyed but only passed on from one form to another
What is kinetic energy? [1]
energy due to motion - movement energy
What is the unit for energy? [1]
Joules (J)
What is the formula for kinetic energy? [2]
K.E. = 1/2mv^2
What are the 3 types of potential energy? [3]
- gravitational potential energy (GPE)
- elastic potential energy
- electric potential energy
What is GPE? [2]
- energy posessed by the object due to their height
- height of object from surface of the earth
What is the formula for GPE? [1]
GPE = mgh
What is mechanical energy? [1]
the sum of kinetic energy and potential energy
What is the formula for mechanical energy? [2]
mechanical energy = kinetic energy + potential energy
What is mechanical or electrical work done equal to? [1]
the energy transferred
What is the formula for work done? [2]
force x distance moved in the direction of the force
What are non-renewable fossil fuels? [3]
- coal
- oil
- natural gas
What are renewable energy resources? [5]
- hydroelectric
- wind
- geothermal
- solar
- biofuels
What is the main source of energy for most energy resources? [1]
sun
What energy resources don’t need the sun as the source of energy? [3]
- geothermal
- nuclear
- tidal
How is energy released from the sun? [1]
nuclear fusion
How is energy released in nuclear reactors? [1]
nuclear fission
What are the formulas for efficiency? [2]
efficiency = (useful energy output / total energy input) x 100
efficiency = (useful power output / total power input) x 100
What is power? [2]
- work done per unit time
- energy transferred per unit time
What is the unit for power? [1]
Watt (w)
What are the formulas for power? [2]
power = work done / time taken
power = energy transformed / time taken
What is pressure? [1]
force per unit area
What is the formula for pressure? [2]
pressure = force / area