Electrical Basics Quiz

What is the unit of electrical current?

• Volt

• Ohm

• Ampere

• Watt

What is the unit of electrical resistance?

• Ohm

• Ampere

• Volt

• Watt

What does Ohm’s Law state?

• V = I × R

• V = R/I

• I = V × R

• P = V + I

If voltage is 12V and resistance is 3 ohms, what is the current?

• 36A

• 4A

• 0.25A

• 15A

What is the symbol for a battery in a circuit diagram?

• Circle with a cross

• Zigzag line

• Parallel long and short lines

• Triangle pointing down

What type of current flows in only one direction?

• AC

• DC

• Oscillating

• Inverted

What does a fuse do in a DC circuit?

• Increases voltage

• Amplifies current

• Protects against overcurrent

• Switches polarity

What device stores electrical energy in a DC circuit?

• Resistor

• Inductor

• Capacitor

• Diode

What is the primary function of a resistor?

• Increase voltage

• Store energy

• Limit current

• Switch polarity

In DC systems, polarity is important because:

• Current changes direction

• Components may be damaged if reversed

• Voltage is too high

• Resistance varies with polarity