This diagram shows three capacitors connected in series with a cell of e.m.f. 1 . 5 V . Calculate the charges Q 1 to Q 6 on each of the plates.

Equivalent capacitance, 1 C = 1 100 + 1 200 + 1 600 ⇒ 1 C = 6 + 3 + 1 600 ⇒ C = 60 μ F Charge stored, Q = C × V ⇒ Q = 60 × 10 - 6 × 1 . 5 ⇒ Q = 90 μ C So, Q 1 = + 90 μ c , Q 2 = - 90 μ C . Q 3 = + 90 μ C Q 4 = - 90 μ c , Q 5 = + 90 μ C . Q 6 = - 90 μ C

This diagram shows three capacitors connected in series with a cell of e.m.f. 1 . 5 V . Calculate the p.d. across each capacitor.

Equivalent capacitance, 1 C = 1 100 + 1 200 + 1 600 ⇒ 1 C = 6 + 3 + 1 600 ⇒ C = 60 μ F Charge stored, Q = C × V ⇒ Q = 60 × 10 - 6 × 1 . 5 ⇒ Q = 90 μ C So, Q 1 = + 90 μ c , Q 2 = - 90 μ C . Q 3 = + 90 μ C Q 4 = - 90 μ c , Q 5 = + 90 μ C . Q 6 = - 90 μ C Using V = Q C Potential Difference = 0 . 90 V across the 100 µ F capacitor, 0 . 45 V across the 200 µ F capacitor, 0 . 15 V across the 600 µ F capacitor.

This is a circuit used to investigate the discharge of a capacitor, and a graph showing the change in current with time when the capacitor is discharged. The charge on the capacitor is equal to the area under the graph. Estimate the charge on the capacitor when the potential difference across it is 9 . 0 V .

This is a circuit used to investigate the discharge of a capacitor. The charge on the capacitor is equal to the area under the graph. The charge on the capacitor when the potential difference across it is 9 . 0 V . Evidence of using the area 45 ± 5 m C Hence, it is the required answer.

MEDIUM

AS and A Level

IMPORTANT

Earn 100

A $4700 µ F$ capacitor has a p.d. of $12 V$ across its terminals. It is connected to a resistor and the charge leaks away through the resistor in $2.5 s$ . Suggest why the last two quantities can only be estimates

Important Questions on Capacitance

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 10

An electronics engineer is designing a circuit in which a capacitor of capacitance of

4700 μ F

is to be connected across a potential difference of

9.0 V

. He has four

4700 μ F, 6 V

capacitors available. Draw a diagram to show how the four capacitors could be used for this purpose.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 11

Calculate the different capacitances that can be made from three

100 μ F

capacitors. For each value, draw the network that is used.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 12

This diagram shows three capacitors connected in series with a cell of e.m.f. $1.5 V$ .

Question Image

Calculate the charges $Q_{1}$ to $Q_{6}$ on each of the plates.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 12

This diagram shows three capacitors connected in series with a cell of e.m.f. $1.5 V$ .

Question Image

Calculate the p.d. across each capacitor.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 13

(a) State one use of a capacitor in a simple electric circuit.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 13

This is a circuit used to investigate the discharge of a capacitor, and a graph showing the change in current with time when the capacitor is discharged.

Question Image

Deduce the resistance $R$ of the resistor.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 13

This is a circuit used to investigate the discharge of a capacitor, and a graph showing the change in current with time when the capacitor is discharged.

Question Image

Explain why the current decreases as the capacitor discharges.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 23 - Capacitance>EXAM-STYLE QUESTIONS>Q 13

This is a circuit used to investigate the discharge of a capacitor, and a graph showing the change in current with time when the capacitor is discharged.

Question Image

The charge on the capacitor is equal to the area under the graph. Estimate the charge on the capacitor when the potential difference across it is $9.0 V$ .

A 4700 µF capacitor has a p.d. of 12 V across its terminals. It is connected to a resistor and the charge leaks away through the resistor in 2.5 s. Suggest why the last two quantities can only be estimates

Important Questions on Capacitance

Learn and Prepare for any exam you want !

A $4700 µ F$ capacitor has a p.d. of $12 V$ across its terminals. It is connected to a resistor and the charge leaks away through the resistor in $2.5 s$ . Suggest why the last two quantities can only be estimates