An electric circuit is designed to carry a current of $10 \mathrm{A}$. If the circuit is required to carry a higher current, how should the wiring be changed? Explain your answer.

a) What does LDR stands for?

b) Draw its circuit symbol.

c) What happens to the resistance of an LDR when light is shone on it?

Redraw the circuit shown below by including a light-dependent resistor in place of the thermistor.

 Explain why the bell would be silent when the LDR is in darkness.

Explain why the bell would ring when light shines on the LDR.

Two resistors are to be connected to form a potential-divider circuit. Should they be connected in series or in parallel with each other?

State briefly the function of a potential- divider circuit.