Practise questions | Salam Academy

SA-9702-CA1-0022 marksL2 StandardCalculatorCombining capacitors

A

3.0

μF capacitor is in series with a parallel combination of

2.0

μF and

4.0

μF. Calculate the total capacitance.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-CA1-0052 marksL2 StandardCalculatorCapacitance

Calculate the capacitance of an isolated sphere of radius

0.15

m, in pF. (

\varepsilon_0=8.85\times10^{-12}

F m⁻¹)

Salam Academy Original Practice · Proposed mark scheme

SA-9702-CA2-0022 marksL2 StandardCalculatorEnergy stored

A

500

μF capacitor discharges from

12

V to

6.0

V. Calculate the energy released, in mJ.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-CA3-0022 marksL2 StandardCalculatorExponential discharge

A capacitor at

12

V discharges with time constant

2.0

s. Calculate the p.d. after

3.0

s.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-CA3-0032 marksL2 StandardCalculatorExponential discharge

For the same capacitor (

12

V,

RC=2.0

s), calculate the time for the p.d. to fall to

3.0

V.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-CM1-0052 marksL2 StandardCalculatorv = rω

The Moon orbits Earth with period

27.3

days. Calculate its angular speed, in units of

10^{-6}

rad s⁻¹.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-CM2-0051 markL2 StandardCalculatorCentripetal force

A ball on a string moves in a circle at constant speed. The work done by the tension during one revolution is

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC1-0032 marksL2 StandardCalculatorInternal resistance

A battery's terminal p.d. is

9.0

V on open circuit and

8.4

V when it supplies a current of

1.2

A. Calculate its internal resistance.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC1-0051 markL2 StandardCalculatorV–I graph of a cell

A cell has e.m.f.

6.0

V and internal resistance

1.5

Ω. Calculate the short-circuit current.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC2-0022 marksL2 StandardCalculatorCombining resistors

A

4.0

Ω resistor is in series with a parallel combination of

6.0

Ω and

3.0

Ω across a

12

V supply of negligible internal resistance. Calculate the supply current.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC2-0031 markL2 StandardCalculatorKirchhoff's laws

In the circuit of the previous question (

2.0

A from the supply), calculate the current in the

3.0

Ω resistor.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC3-0022 marksL2 StandardCalculatorPotential dividers

A potential divider has

R_1=4.7

kΩ and a

12

V supply. Calculate the value of

R_2

that gives an output of

4.0

V across

R_2

, in kΩ.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC3-0031 markL2 StandardCalculatorPotential dividers

A potential divider consists of a fixed resistor and an NTC thermistor. As the temperature rises, the p.d. across the fixed resistor

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC3-0041 markL2 StandardCalculatorPotential dividers

An LDR and a fixed resistor form a potential divider. To get an output that rises as it gets darker, the output should be taken across

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DC3-0052 marksL2 StandardCalculatorPotentiometers

A cell of e.m.f.

1.02

V balances at

51.0

cm on a potentiometer wire. Another cell balances at

75.0

cm. Calculate the e.m.f. of the second cell.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DS1-0032 marksL2 StandardCalculatorYoung modulus

Using a stress of

8.0\times10^7

Pa and a strain of

4.0\times10^{-4}

, calculate the Young modulus, in GPa.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DS1-0042 marksL2 StandardCalculatorYoung modulus

A wire has a diameter of

0.50

mm. Calculate its cross-sectional area, in units of

10^{-7}

m².

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DY1-0042 marksL2 StandardCalculatorNewton's laws

A

0.15

kg cricket ball travelling at

30

m s⁻¹ is caught and brought to rest in

0.050

s. Calculate the average force on the ball.

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DY1-0051 markL2 StandardCalculatorNewton's laws

A book rests on a table. Which pair of forces is a Newton's third-law pair?

Salam Academy Original Practice · Proposed mark scheme

SA-9702-DY2-0022 marksL2 StandardCalculatorElastic collisions

For the same collision (

3.0

kg at

4.0

m s⁻¹ hits

1.0

kg at rest; both move off at

3.0

m s⁻¹), calculate the kinetic energy lost.

Salam Academy Original Practice · Proposed mark scheme

Question bank