III: Q3 OHM'S LAW

The statement which correctly represents Ohm’s law:

• V = IR

• V = R/I

• V = R/I

• I = R/V

An electric kettle with 50-Ω heat element is powered by a 230-V wall outlet. The current flowing through kettle is:

• 0.217 A

• 4.6 A

• 10.86 A

• 11500 A

If doubling the voltage across a resistor doubles the current through the resistor, then

• the resistor value decreased

• the resistor value did not change

• the resistor value increased

• it is impossible to determine the change in the resistor value

If the voltage across a fixed value of resistance is increased five times, what does the current do?

• It increases by a factor of five.

• It decreases by a factor of five.

• It stays the same.

• Not enough information

If the resistance in a circuit with constant voltage increases, the current will...

• increase

• decrease

• its stays the same

• not eneough information

Are the resistors shown connected in parallel or in series?

• The resistors are connected in parallel because the same current flows through all three resistors.

• The resistors are connected in parallel because different current flows through all three resistors.

• The resistors are connected in series because the same current flows through all three resistors.

• The resistors are connected in series because different current flows through all three resistors.

Give a verbal expression for Ohm’s law.

• Ohm’s law says that the current through a resistor equals the voltage across the resistor multiplied by the resistance of the resistor.

• Ohm’s law says that the voltage across a resistor equals the current through the resistor multiplied by the resistance of the resistor.

• Ohm’s law says that the resistance of the resistor equals the current through the resistor multiplied by the voltage across a resistor.

• Ohm’s law says that the voltage across a resistor equals the square of the current through the resistor multiplied by the resistance of the resistor.

Two identical resistors are connected in parallel across the terminals of a battery. If you increase the resistance of one of the resistors, what happens to the current through and the voltage across the other resistor?

• The current and the voltage remain the same.

• The current decreases and the voltage remains the same.

• The current and the voltage increases.

• The current increases and the voltage remains the same.

What are the two types of connection which binds electrical devices in a circuit?

• Series – Parallel

• Chain – Cyclic

• Open - Closed

• Current - Voltage

When you remove a bulb from a three-bulb circuit, and the other two bulbs go off, then the bulbs must have been connected in __________.

• Parallel

• Series

• Open

• Closed