C9KirchhoffsLaws

The diagram shows a network consisting of three resistors.

What is the combined resistance of the network between terminal X and terminal Y?

• 0.67 kΩ

• 1.6 kΩ

• 3.2 kΩ

• 8.1 kΩ

Four resistors, each of resistance R, are connected as shown.

The total resistance between point X and point Y is 120 .

What is the magnitude of the resistance R ?

• 30 Ω

• 90 Ω

• 160 Ω

• 480 Ω

The diagram shows a circuit with a cell and three resistors with resistances R1, R2 and R3.

The cell has negligible internal resistance.

The total resistance of the circuit is RT.

Which equation for RT is correct?

• 
• 
• 
• 

• A

• B

• C

• D

Which description of Kirchhoff’s first law is correct?

• It considers the currents at a junction in a circuit and is a consequence of the conservation of

  charge.

• It considers the currents at a junction in a circuit and is a consequence of the conservation of

  energy.

• It considers the electromotive forces and potential differences in a circuit loop and is a

  consequence of the conservation of charge.

• It considers the electromotive forces and potential differences in a circuit loop and is a

  consequence of the conservation of energy.

Two resistors of resistances r and R are connected in parallel.

The value of r is less than that of R.

Which statement about the combined resistance of the two resistors is correct?

• It is between r and R.

• It is equal to (r + R).

• It is greater than (r + R).

• It is less than r.

The diagram shows four identical resistors connected in a circuit.

Which resistor dissipates the most power?

• A

• B

• C

• D

A student builds the circuit shown. All the lamps are identical.

Which lamp dissipates the most power?

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D