Understanding Resistance in Electric Circuits

What is meant by resistance in an electric circuit?

• The speed of electrons in a circuit

• The potential difference required to drive a current through a component

• The amount of light produced by a lamp

• The total energy stored in a battery

What is the unit of resistance?

• Volt

• Ampere

• Ohm

• Joule

Which equation is used to calculate resistance?

• Resistance = Current / Potential Difference

• Resistance = Current x Potential Difference

• Resistance = Potential Difference / Current

• Resistance = Potential Difference + Current

If a lamp has a potential difference of 10 volts and a current of 1 ampere, what is its resistance?

• 10 ohms

• 5 ohms

• 20 ohms

• 1 ohm

What happens when electrons collide with atoms in a metal?

• Electrical energy is transferred into other forms of energy

• They increase in speed

• They stop moving

• They produce sound energy

What is the potential difference across a lamp if the current is 0.5 amperes and the resistance is 50 ohms?

• 50 volts

• 10 volts

• 25 volts

• 100 volts

In a circuit, what does a potential difference of 9 volts indicate?

• The lamp produces 9 watts of power

• The current carries 9 joules of electrical energy per coulomb of charge

• The current is 9 amperes

• The circuit has 9 ohms of resistance

What is the resistance of a lamp if the potential difference is 1 volt and the current is 1 ampere?

• 0.5 ohms

• 1 ohm

• 10 ohms

• 2 ohms

Why does lamp B have a higher resistance than lamp A?

• It has a higher current

• It has a lower potential difference

• It requires more energy to drive the current

• It requires less energy to drive the current

What is the flow of electrons around a circuit called?

• Power

• Voltage

• Resistance

• Current