Question 1: What would happen if the resistance (hindrance) suddenly became less?
A. Nothing would change, and the system would work as usual.
B. Voltage and current would be equivalent to each other
C. The circuit would break
D. None of the above
Answer Analysis
The correct answer is C.
The circuit would break. As per the ohm’s law, R=I/V, if the resistance suddenly becomes significantly less or none, that would mean that the voltage of the system an increase substantially. This would mean that it would probably trip a circuit breaker or blow a fuse.
Question 2: Suppose an electric current of 1 microamp (1 μA) was to go through a resistance of 3 mega-ohms (3 MΩ). How much voltage would be “dropped” across this resistance?
A. 3.0 volts
B. 3.45 volts
C. 30 volts
D. 34.5 volts
Answer Analysis
The correct answer is A.
1×10−6 amps of current through a resistance of 3X106 Ω will produce a voltage “drop” equal to 3.0 volts. Using the formula V= IR
Question 3: How current and voltage are experienced in resistor 1 if two resistors are placed in parallel and resistor 1 has twice the resistance as resistor 2.
A. Voltage remains the same, and current decreases
B. Current remains the same, and voltage increases
C. Both current and voltage remain the same
D. Both current and voltage increases
Answer Analysis
The correct answer is A.
The electric potential difference across each resistor (ΔV) is the same in parallel circuits. The current in a resistor follows Ohm's law: I = ΔV / R. Since the ΔV is the same for each resistor, the current will be smallest where the resistance is greatest.