Igcse Physics (Double Award) Revision in Details

Physics revision

Section 1: Forces and motion

kilogram (kg), metre (m), metre/second (m/s), metre/second2 (m/s2), newton (N), second (s),  newton per kilogram (N/kg)

Section 2: Electricity

ampere (A), coulomb (C), joule (J), ohm (Ω), second (s),volt (V), watt (W).

Section 3: Waves

degree (0), hertz (Hz), metre (m), metre/second (m/s), second (s).

Section 4: Energy resources and energy transfer

kilogram (kg), joule (J), metre (m), metre/second (m/s), metre/second2 (m/s2), newton (N), second (s), watt (W).

Section 6: Magnetism and electromagnetism

ampere (A), volt (V), watt (W).

Equations to Learn

• average speed=distancetime

• force=mass ×acceleration                                           acceleration= change in velocitytime taken

•  momentum=mass ×velocity                  P=M× V

•   work done=force×distance moved in the direction of the force

• energy transferred = work done      kinetic energy= ½×mass×speed2        gravitational potential energy=mass×g×height

• weight=mass×gravitational field strength

• moment=force×perpendicular distance from the pivot

• charge=current×time                        voltage=current×resistance              electrical power=voltage×current

• wave speed=frequency×wavelength

• input (primary)voltageoutput (secondary)voltage=primary turnssecondary turns

• the relationship between refractive index, angle of incidence and angle of refraction:

n=sin i sin r

• the relationship between refractive index and critical angle:

• sin c= 1n

• efficiency=useful energy outputtotal energy output

• input power=output power

• VPIP=VSIS for 100% efficiency

Equations Given

Plotting distance-time graph-

Plotting

• Distance must be on the y axis

• Time must be on the x axis

Interpreting

• Straight horizontal line (--) means the object is stationary

• Diagonal line upwards ( / ) means the object is moving forwards. The steeper the line, the faster it is moving.

• Diagonal line downwards ( \ ) means the object is moving backwards. Again, the steeper the line, the faster it is moving.

• A curve upwards also means there is an acceleration, a downwards curve means a deceleration

Experiment Investigating Motion-

• Take a toy wind-up car and put it next to a ruler that is a meter long

• Wind up the toy car x amount of times

• Every 5 seconds, record distance travelled by car

• Plot a graph (distance time graph)

Plotting Velocity-Time Graph-

Plotting

• Velocity on y axis

• Time on x axis

Interpreting

• Diagonal line going upwards = acceleration

• Diagonal line going downwards = deceleration

• Horizontal straight line = constant speed (but not necessarily terminal velocity)

• The steeper the line, the more acceleration/deceleration

Acceleration from the gradient of from velocity-time graph

acceleration = the gradient of the graph

gradient = rise / run

acceleration = change in y (velocity) / change in x (time)

Distance travelled from the area between a velocity-time graph

On a velocity time graph the area between a line and the axis represents the distance the object has travelled in that time. If the shape is awkward remember to split it up into sections.

 Area of a triangle: ½ x base x height

Area of a rectangle: base x height

Effect of Forces-

changes in speed

- when an object is stationary it has the…