Circuit Components and Connections Assessment

A rheostat with maximum resistance of 100Ω is adjusted to 75% of its maximum length. What is its approximate resistance?

• 25Ω
• 50Ω
• 75Ω
• 100Ω

In a series circuit with three resistors (10Ω, 20Ω, and 30Ω), if the current through the 10Ω resistor is 2A, what is the current through the 30Ω resistor?

• 0.67A
• 2A
• 6A
• 60A

If three 6V cells are connected in series, what is the total EMF?

• 2V
• 6V
• 12V
• 18V

Two resistors (4Ω and 12Ω) are connected in parallel. What is their equivalent resistance?

• 3Ω
• 8Ω
• 16Ω
• 48Ω

Why might a rheostat be useful in a circuit with a DC motor?

• To increase voltage only
• To control the motor's speed
• To store electrical energy
• To reverse the motor's direction

If a 12V battery sends current through two 6Ω resistors in series, what is the voltage across each resistor?

• 3V
• 6V
• 12V
• 24V

What happens to the total resistance when resistors are connected in parallel?

• It increases
• It decreases
• It stays the same
• It becomes zero

In a parallel circuit with two branches, if one branch has 2A current and the other has 3A, what is the total current?

• 1A
• 2.5A
• 5A
• 6A

Three identical cells, each with internal resistance of 0.5Ω, are connected in series. What is their total internal resistance?

• 0.5Ω
• 1.0Ω
• 1.5Ω
• 2.0Ω

When using a rheostat to control current, what happens when you increase the length of wire in the circuit?

• Current increases
• Current decreases
• Voltage increases
• Temperature increases