# Physics Test - Circuits

Series Circuit
- has only one path for the electrical current to take
1 of 14
Current in Series
-is the same at all positions in the circuit
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Voltage in Series
-supply voltage is equal to the voltage of other components added together, Vs = V1 + V2 + V3...
3 of 14
Parallel Circuits
-has more than one path for the electrical current to take
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Current in Parallel
-total Current is equal to the sum of the currents in the branches, It = I1+I2+I3
5 of 14
-lights can be switched on and off dependently, if one light no longer works the rest can remain on, all lights get the same voltage so can be the same brightness
6 of 14
Voltage and Current
-As voltage increases, current decreases
7 of 14
Resistance
-is the opposition to current, measured in ohms, symbol R
8 of 14
Ohmeter
- used to measure resistance, must be connected in parallel
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Resistance Effects
-will cause wires and components to heat up because if converts some of the electrical energy into heat energy -useful in kettle or toaster - not useful in computer as fan will be needed to cool it down
10 of 14
Wires and Resistance
-the thicker the wire the lower the resistance
11 of 14
Variable resistance
-a device which changes the resistance in the circuit -By using a longer wire, the resistance increases
12 of 14
Uses for Variable resistance
-brightness control -sound level control -speed control -temperature control
13 of 14
Ohms Law
V=IR - Volatage = Current times Resistance
14 of 14

## Other cards in this set

### Card 2

#### Front

-is the same at all positions in the circuit

#### Back

Current in Series

### Card 3

#### Front

-supply voltage is equal to the voltage of other components added together, Vs = V1 + V2 + V3...

### Card 4

#### Front

-has more than one path for the electrical current to take

### Card 5

#### Front

-total Current is equal to the sum of the currents in the branches, It = I1+I2+I3