Electric Current and Circuit Components Assessment

If 5 Coulombs of charge flow through a circuit in 2.5 seconds, what is the current in amperes?

• 2 A
• 12.5 A
• 0.5 A
• 7.5 A

Why is conventional current direction opposite to electron flow?

• Because electrons are negatively charged
• Due to historical misconceptions about charge carriers
• Because protons flow in the opposite direction
• Because current always flows clockwise

A voltmeter reads 12V across a component with a current of 3A. What is the resistance according to Ohm's Law?

• 36 Ω
• 4 Ω
• 0.25 Ω
• 15 Ω

Why do ammeters have very low resistance?

• To minimize power consumption
• To avoid altering the current they're measuring
• To protect the circuit
• To increase measurement accuracy

What happens to the resistance of two identical wires if one is stretched to twice its original length?

• The stretched wire's resistance doubles
• The stretched wire's resistance halves
• The resistance remains the same
• The resistance increases by four times

If 10 Joules of energy are transferred by 5 Coulombs of charge, what is the potential difference?

• 2 V
• 50 V
• 0.5 V
• 15 V

How does the cross-sectional area of a wire affect its resistance?

• As area increases, resistance increases
• As area increases, resistance decreases
• Area has no effect on resistance
• The relationship is random

What distinguishes EMF from potential difference?

• EMF is energy gained per coulomb, PD is energy lost per coulomb
• EMF only occurs in batteries, PD only in wires
• EMF is measured in amperes, PD in volts
• There is no difference

Why are voltmeters connected in parallel rather than series?

• To measure current accurately
• To avoid affecting the circuit's current
• Because it's easier to install
• To reduce power consumption

What happens to the resistance of a copper wire if its temperature increases?

• Resistance increases
• Resistance decreases
• Resistance stays the same
• Resistance drops to zero