Units and Vocabulary
What unit is used to measure electric current?
Ampere
What happens if a circuit is broken anywhere in a series circuit?
The entire circuit stops working
What happens to current if resistance increases and voltage stays the same?
Current decreases
What unit is used to measure electrical power?
Watt
What type of charge do electrons have?
Negative
What force causes electric charges to move in a circuit?
Voltage
Why are most household circuits wired in parallel?
So devices work independently and one failure doesn’t shut everything off
What is Ohm’s Law?
V = IR
What formula is used to calculate electrical power?
P = IV
What poles does every magnet have?
A north pole and a south pole
Which material is the best conductor: rubber, glass, copper, or wood?
Copper
What happens to other bulbs in a parallel circuit if one bulb goes out?
The other bulbs stay on
A circuit has 12 V and 3 Ω resistance. What is the current?
4 A
What is being measured when a device uses watts over time?
Electrical energy usage
What type of current flows in one direction only?
Direct current (DC)
What electrical property is measured in ohms?
Resistance
Why is current the same everywhere in a series circuit?
Because there is only one path for current to flow
A circuit has 9 V and 0.5 A. What is resistance?
18 Ω
A 60 W bulb runs for 10 hours. What energy is used?
600 Wh
What happens when like charges are brought close together?
They repel each other
What is the difference between voltage and current?
Voltage is energy per charge; current is flow of charge
Why use parallel circuits in real life?
So devices operate independently and don’t all shut off together
A device uses 120 V and 2 A. What is resistance?
60 Ω
Why do high-power appliances need thicker wires?
To reduce resistance and prevent overheating
How is an electromagnet made stronger?
More current, more coils, or an iron core