formulas
formula of speed
Distance / time
Principal of moments
When a body is in equllibrum, the sum of clockwise moments about a pivot is = to the sum of anticlockwise moments about the same pivot
Explain conduction
The process of energy transfer where energy is transferred through the passing on of vibrational motion from one particle to another
Define a wave
A disturbance that propagated to space, waves transfer energy without transferring matter
Name the electromagnetic waves in order
Radio waves, microwaves, infrared, visible light, ultra violet, x rays, gammarays
acceleration
F=ma
Kinetic particle model
Is made up of tiny particles that are in continuous motion
Why does a vaccum prevent conduction?
As there are no particles present, thus thermal energy can not be transferred
The definition of Longitudinal waves
The direction to propagation is parallel to the direction of oscillation
The volume of water plumper per minute from a reservoir to the late is 780m3. The water raised through a vertical height of 5.50m. Water has a density of 1000 kg/m3.
Calculate the mass of water plumper per minute into the lake
Mass= dxu
M= 1000x780=780000
Pressure
P=f/a
Principal of conservation of energy
Energy can not be created of destroyed, energy can be transferred from one store to another. The total energy of an isolated system is constant
Explain convection currents
When a liquid is heated, it expands and increases in volume. As volume increases, density decreases. The warm liquid, being less dense than it's surrounds, will rise. The cold liquid being denser will sink. This difference in density results in convection currents
What is a wave front?
An imaginary surface representing corresponding points of a wave
Name one wave motion and it's meaning
Transverse: wave has a direction of vibration that is perpendicular to the direction of wave travel
Longitudinal: wave of has a direction of vibration that is parellel to the direction of wave travel
Size of an energy store
Ek = 1/2 mv2 OR Ep=mgh
Center of gravity
Is when an object is an imaginary point where the entire wight of the object seems to act
Name how thermal wear reduces loss of thermal energy through conduction, convection and radiation
Conduction: the plastic strops obstructis the flow of air, therefore reducing conduction/ the rate conduction
What is the formula of speed?
U=f-1
Is the speed of sound in solid > in liquid > in gas?
Yes
Power
P = w/t = e/t
Thermal equllibrum
Describes a state in which two or more objects have the same temperature and that there is no net transfer of energy between them
Explain why an object must be given thermal energy when it melts even though the temperature does not change while it is melting
When a substances changes temperature, the change in energy in its internal energy store needs to be overcome (bro I lowkey don't even know)
What is the displacement distance graph
Shows the displacement of all particles at one time
Explain why an objects speed slowly decreases
Since there is no upward force acting on it continuously and only weight acting on it, by newton's 2nd law where f=mg, ma=w therefore acceleration is negative, which means that the object will slow down