Electrical systems (with resistance)

Which of the following correctly matches the SI unit of a quantity and the electrical component that is related to it?

• A

• B

• C

• D

Which of the following statement about resistance is false?

I. the SI unit of resistance is the ohm.

II. Variable resistors are the only type of resistors.

III. resistance slows down the current flow in a circuit.

• I only

• II only

• III only

• none of the above

Which of the following statements about electricity is false?

• Electricity can be dangerous if precautions such as using a fuse are not taken.

• Electricity can cause a fuse to blow.

• Electricity can be used to coat and disinfect metal objects.

• Electricity can be used to destroy electromagnets.

The figure below shows an electric kettle with a heating element.

Which of the following describes the properties that the heating element should possess?

• A

• B

• C

• D

Study the circuit below.

Which electrical component is NOT found in the circuit?

• Ammeter

• dry cell

• variable resistor

• wire

Which of the following describe(s)how an ammeter should be connected in a circuit?

• Negative terminal of battery connected to the negative terminal of ammeter

• Negative terminal of battery connected to the positive terminal of ammeter

• Positive terminal of battery connected to the negative terminal of ammeter

• All of the above

Bill wants to measure the potential difference across a bulb. Which component does he need to include in his circuit?

• A

• B

• C

• D

Which of these are safety precaution for handling electricity in households?

I. putting multiple plugs into one socket

II. installing a circuit breaker

III. Placing an oven on a wet surface.

IV. Replacing a phone charger when its wires wear out

• I and II only

• I and III only

• II and IV only

• III and IV only

Study the circuit below. The ammeter reading is 5.0A when the bulb lights up.

What will the ammeter reading be if the bulb fuses?

• 0A

• 1 A

• 4 A

• 5 A

Given that all the resistors in the two circuits, including the variable resistor, have the same resistance, which bulb will be brighter?

• Bulb A

• Bulb B

• Both bulbs will have equal brightness

• Both bulbs will not work.