Physics Concept Map
Motion and Forces
Wave
Electromagnetic spectrum and light
Energy
Vectors/Scalars
Graphs
Speed/Acceleration
Distance/Time
Vector quantities have both magnitude and direction
Scalar quantities have only magnitude
Speed
Time
Mass
Velocity
Weight
Acceleration
Graph that displays how far an object has travelled over a period of time
Speed calculated by the gradient of a line
Velocity/Time
Graph that displays the direction of and how fast an object has travelled over a period of time
Distance calculated by the area under the line
Speed
Acceleration
Calculated by dividing distance by time. Most common unit is m/s.
Calculated by dividing difference in velocity divided by time. Most common unit is m/s^2 (metres per second per second).
Forces
Newton's Laws
Resultant forces
Momentum
Stopping distance
Newton's Second Law: The change of motion of an object is proportional to the force impressed; and is made in the direction of the straight line in which the force is impressed.
Newton's Third Law: To every action there is always opposed an equal reaction; or, the mutual actions of two bodies upon each other are always equal, and directed to contrary parts
Newton's First Law: Every body continues in its state of rest, or of uniform motion in a straight line, unless it is compelled to change that state by forces impressed upon it
An object in motion will remain in motion until it is acted upon by an external force. A stationary object will remain stationary until it is acted upon by an external force.
The force acting on an object is equal to it's mass multiplied by it's acceleration
When two objects interact, they apply a force of equal magnitude to each other in opposite directions
The tendency of an object to continue moving in the same direction. Calculated by the mass of the object multiplied by the velocity. Most common unit is Kg m/s.
Conservation of momentum
Work out momentum of both objects before collision. Then do total momentum/total mass to figure out velocity after collision.
When two or more forces are acting on an object, the difference between opposite forces can be calculated to find the resultant force.
Stopping distance is equal to thinking distance plus braking distance
Factors affecting thinking distance
Factors affecting braking distance
Age
Fatigue
Visibility
Reaction time
Drug use
Distractions
Friction
Vehicle condition
Energy Stores
Energy Transfers
Efficiency
Renewable/Non-renewable
Kinetic
Chemical
Thermal
Magnetic
Electrostatic
Gravitational potential
Elastic potential
Nuclear
Mechanical: A force moving an object for a distance
Electrical: Charges moving due to potential difference
Conduction: Temperature difference caused electrically or chemically
Radiation: Energy transferred as a wave
Renewable resources are resources that can be used near-indefinitely and usually pose very little to no threat to the environment. Examples include solar power, hydro power, biothermal energy, land power (geothermal), sea power, desert power
Efficiency is calculated by total useful energy/total energy input x 100. It is usually expressed as a percentage.
Waves are a way of transferring energy through oscillations ("vibrations") around a point.
Types of waves
Wave speed
Wave speed is calculated by multiplying frequency (Hz) by wavelength (Lambda). Frequency is found by calculating how many wavelengths pass a certain point per second.
Longitudinal
Transverse
In transverse waves oscillations are perpendicular to the direction of wave travel. The wavelength is calculated by the distance between two crests.
In longitudinal waves vibrations are parallel to the direction of wave travel. The wavelength is calculated by the distance between two compressions (the length of a rarefaction).
Seismic S waves
Ripples on the surface of a liquid
Electromagnetic waves
Sound waves
Seismic P waves
Microwaves
Radio waves
Infrared
Visible light
Ultraviolet
X rays
Gamma rays
Used for communication through radio or video. Virtually harmless
Used for radar, cooking, and various signals. Hazard is internal tissue heating
Used for night vision and transferring heat from sources. Hazard is heat experienced through radiation.
Used to see. Hazard is possible blindness depending on brightness.
Used for killing bacteria, curing inks and resins, and authentication measures. Hazard is sunburn or in some cases, skin cancer.
Used for sterilising food and medical equipment. Hazard is the same as x-rays but to a much greater extent.
Used for looking inside organisms. Hazard is damaging cells by causing mutations which can lead to cancer.
We see colour because objects absorb some colours and reflect others. If an object absorbs every colour except blue, it is seen as blue.
Lenses can be used to correct or alter the size of images. Concave lenses converge light rays bringing images into focus. Convex lenses diverge light rays bringing images out of focus or projecting them larger than they actually are.