What is the unit of electrical resistance?
Amp
Ohm
Volt
Which equation correctly links voltage V, current I and resistance R?
V = I x R
V = I ÷ R
V = R ÷ I
A current of 0.5 A flows through a 22 Ω resistor. What is the value of the voltage across it?
0.23 V
11 V
44 V
A current of 0.3 A flows through a 12 V lamp. What is the resistance of the lamp?
0.04 Ω
3.6 Ω
40 Ω
What happens to the resistance of a metal conductor as its length increases?
Resistance remains unchanged.
Resistance increases.
Resistance decreases.
Higher Tier only:
What happens to the resistance of a metal conductor as its cross section area decreases?
A 15 m length of wire is found to have a resistance of 20 Ω. What is the resistance of an identical wire of length 60 m?
5 Ω
80 Ω
240 Ω