Ohm's Law Quiz

What does Ohm's law state about the relationship between potential difference and current in a conductor?

• The potential difference is inversely proportional to the current.

• The potential difference is equal to the current.

• The potential difference is proportional to the current.

• The potential difference is unrelated to the current.

Answer explanation

Ohm's law states that the potential difference is proportional to the current in a conductor.

According to Ohm's law, what is the formula for calculating voltage (V)?

• V = I / R

• V = I + R

• V = I × R

• V = R / I

Answer explanation

Answer Explanation highlighting the correct choice: V = I × R

What is the formula for calculating resistance (R) according to Ohm's law?

• R = V × I

• R = V / I

• R = I / V

• R = I × V

Answer explanation

The correct formula for calculating resistance (R) according to Ohm's law is R = V / I, where R is resistance, V is voltage, and I is current.

In the context of Ohm's law, what does the symbol 'I' represent?

• Voltage in volts

• Current in amperes

• Resistance in ohms

• Power in watts

Answer explanation

In the context of Ohm's law, the symbol 'I' represents Current in amperes, making it the correct choice.

What is the unit of resistance in Ohm's law?

• Volts (V)

• Amperes (A)

• Ohms (Ω)

• Watts (W)

Answer explanation

The unit of resistance in Ohm's law is Ohms (Ω), represented by the symbol Ω.

What is the voltage across a resistor with a resistance of 3 ohms and a current of 2 amperes?

• A) 4 V

• B) 6 V

• C) 10 V

• D) 12 V

Answer explanation

The voltage across a resistor is calculated using Ohm's Law: V = I * R. Therefore, V = 2 A * 3 ohms = 6 V. Hence, the correct answer is B) 6 V.

What is the total voltage across the terminals when the voltages across three resistors are 4 V, 6 V, and 10 V respectively?

• A) 10 V

• B) 15 V

• C) 20 V

• D) 25 V

Answer explanation

The total voltage across the terminals is the sum of the voltages across each resistor, which is 4V + 6V + 10V = 20V. Therefore, the correct answer is C) 20 V.

What is the effect of resistors in series on the voltage across the terminals?

• A) They decrease the total voltage.

• B) They form potential dividers.

• C) They increase the total voltage.

• D) They have no effect on the voltage.

Answer explanation

Resistors in series form potential dividers, affecting the voltage across the terminals by dividing it between the resistors.

In a parallel circuit, how does the overall (total) resistance compare to the lowest resistance in the circuit?

• It is higher than the lowest resistance.

• It is equal to the lowest resistance.

• It is lower than the lowest resistance.

• It is the same as the highest resistance.

Answer explanation

In a parallel circuit, the overall resistance is lower than the lowest resistance due to the multiple paths for current flow, reducing the total resistance.

What becomes constant in parallel circuits?

• Current

• Voltage

• Resistance

• Power

Answer explanation

In parallel circuits, voltage remains constant across all components. This is due to the fact that the voltage across each branch is the same as the total voltage of the circuit.