Physics-electricity

Charge flow (coulumbs, C) = current (Amps, A) x time (seconds, s)


Q = I x t

Ohms law

Potential difference is proportional to current

Ohms laws experiment conclusion- As the potential difference increases, so does the current

Potential difference (V) = current (A) x resistance (ohms- horse shoe)

Rules for series and parallel circuits

Series- connected in 1 loop

-Everywhere in the series circuit, the current is the same
-In series circuit, potential difference is shared between the components

Parallel- Different branches

-Everywhere in a parallel circuit, potential difference is the same (on each branch)
-The current is shared between the components

AC & DC currents

-Potential difference makes current flow through resistors
-High resistor, more energy needed
-Current takes path with less/ low resistance

To not get shocked:
Difference in voltage causes electricity to pass from one to another.
Humans are at 0V. So if we were to touch live wire, we would get an electric shock because of large current.
raise potential difference to be the same as electricity- no current

Plugs
3 types of wires:
-Neutral (blue)- completes the circuit and carries current away. it has 0V
-Earth wire (green + yellow)- Stops appliance casing from becoming live. Provides an alternative pathway, takes the current to flow away, rather than to us. Is normaly at 0V
-If live wire came loose and touched the casing, electric shock.
-Live (brown)- Provides the alternating potential difference from the main supply. Normally at 230V

types of energy stores:
-kinetic
-electrostatic
-gravitational potential
-thermal
-magnetic
-elastic
-nuclear
-chemical

Energy tranferred (J) = Power (W) x time (s)

Power = potential difference x current

Energy = voltage x charge

Charge- a measure of the total current that flowed within a certain period of time

-if any components are disconnected, the whole circuit will stop working

Current = total potential difference / total resistance
I = V/R (rearranged form of ohms law)

components with greater resistnace will always have a higher share of voltage ( more force needed to push charge through areas of higher resistance)

more than 1 loop- more useful than series because as each component has its own loop, if any other components break, the overall circuit is still intact

Vtotal (potential difference) = V1 = V2 = V3...


Itotal (current) = I1 + I2 +I3 ....

loop with greater resistance, have a lower share of current becuase more energy is needed to pass resistor

More components in circuit = lower total resistace

Alternative current (AC)

-The current changes directions
-Current is not constant

Direct current (DC)

Charge is always flowing in the same direction

Either positive or negative

Charge fluctuates between postive and negative