David Sang Solutions for Chapter: Electrical Quantities, Exercise 10: End-of-chapter questions

Electrical appliances are used to transform electrical energy into other, more useful, forms of energy. A lamp is labelled $\text{'}12 \mathrm{V}, 36 \mathrm{W}\text{'}$. How much electrical energy does the lamp transform in $1$ minute?

Electrical appliances are used to transform electrical energy into other, more useful, forms of energy. A lamp is labelled $\text{'}12 \mathrm{V}, 36 \mathrm{W}\text{'}$. It is connected to a $12 \mathrm{V}$ supply. Use the relationship $\mathrm{P}=\mathrm{IV}$ to calculate the current that flows through it.

An electric heater is connected to a $10 \mathrm{V}$ supply. In $20 \mathrm{s}, 30 \mathrm{C}$ of electric charge flows through the heater. Calculate the current flowing.

An electric heater is connected to a $10 \mathrm{V}$ supply. If in $20 \mathrm{s}, 30 \mathrm{C}$ of electric charge flows through the heater, calculate the energy transferred by the heater in $20 \mathrm{s}$.

Draw a diagram of the circuit that you would use to determine the resistance of a coil of wire using a voltmeter and an ammeter. Use conventional symbols and labels the coil clearly.

For a circuit that you would use to determine the resistance of a coil of wire using a voltmeter and an ammeter. State the equation you would use to calculate the resistance of the coil.

State two properties of the wire on which the resistance of the coil depends.

In the diagram, $AB$ is a $0.2 \mathrm{m}$ length of uniform resistance wire, connected into a circuit. Ignore the resistance of the battery.

The current $I$ is $1.5 \mathrm{A}$. Calculate the resistance per metre of the resistance wire in $\mathrm{\Omega }/\mathrm{m}$.