Work And Energy Flashcards
(23 cards)
Define Kinetic energy.
Energy when something is moving
Equation for Kenetic energy.
E = 1/2 x mv^2
Define gravitational potential energy.
The amount of energy on an object due to its position ion a gravitational field
Equation for GPE.
E=mgh
Define Elastic potential. Store or Transfer?
Energy on object has following the deformation of an elastic object due to the application of force. Store
Define Mechanical Energy. Store or Transfer?
Energy Transfer when a force acts on an object. Transfer
Define Radiation energy. Store or Transfer?
Light and sound carry energy and can transfer this between two points. Transfer
Define magnetic energy. Store or Transfer?
Energy due to the force of attraction or repulsion between two magnets. Store.
Define nuclear energy. Store or transfer?
Energy contained in the nucleus of a particle. Store
What is efficiency?
The percentage of energy in the original store transferred to the next store.
Define Work Done.
The amount of energy transferred between two energy stores.
Equation of work done and unit of work done?
W = Fs,
Work done = Force x distance moved in a direction of force.
J, joules
Define power.
The amount of energy transferred per unit of time.
Equation for power. Units?
P = W/s ,
Power = Work done/ Time
Watt
Name Five things that effect thinking distance?
Visibility
Age
Alcohol or Drugs
Eyesight
Fatigue
Emotional state
Name five things that can affect braking distance?
Weather
Quality of breaks
Quality of tires
Road Surface
Speed of vehicle
Equation for breaking distance.
S = V^2 - u^2 / 2a
V^2 = u^2 + 2as
V = Final velocity (will be zero for breaking distance)
U= initial velocity
What is thermal conduction?
Transfer of heat energy through the vibrating of molecules. (Solids)
Driven by difference in temperature
What is conduction reduced and stopped by?
Reduced - Insulator
Stopped - Vacuum, layer of gas
What is thermal convection.
Transfer of thermal energy through the moving of molecules. (Fluids - gas included)
Driven by difference in temperature
What is convection reduced and stopped by?
Reduced- Trapping the liquid or gas in small pockets
Stopped- Vacuum
What is Thermal radiation.
The transfer of heat energy through EM waves.
What is thermal radiation decided and stopped by?
Reduced - Shiny light colored surface, Low surface temperature
Stopped - Nothing
