CAIE IGCSE Physics 1. Motion, forces & energy Question Bank

Practise motion, forces and energy through measurement choices, scalar-vector decisions, speed calculations and force diagrams.

Covered syllabus points

1.1 Physical quantities and measurement techniques 1.2 Motion 1.3 Mass and weight 1.4 Density 1.5.1 Effects of forces 1.5.2 Turning effect of forces 1.5.3 Centre of gravity 1.6 Momentum 1.7.1 Energy 1.7.2 Work 1.7.3 Energy resources 1.7.4 Power 1.8 Pressure

[Maximum number: 1]

A student determines the diameter of a metal ball.
Which apparatus is needed to get an accurate measurement?

a ruler and a protractor

a ruler only

a protractor and a set square

a ruler and two rectangular blocks

[Maximum number: 6]

Fig. 3.1 shows a model of a wind turbine used to demonstrate the use of wind energy to generate electricity. The wind is blowing towards the model, as shown.

Fig. 3.1

(a)

The mass of air passing through the circular area swept out by the turbine blades each second is 7.5 kg . The kinetic energy of the air that passes through this circular area each second is 240 J .

[ 4 ]

(i)

Calculate the speed of the air.

speed =

[ 3 ]

$\mathrm{KE}=\frac{1}{2} \mathrm{mv}^{2}$ in any form $\mathrm{OR} \mathrm{v}^{2}=2 \times \mathrm{KE} / \mathrm{m}$

OR $240=\frac{1}{2} \times 7.5 \mathrm{v}^{2}$

C1

$v^{2}=2 \times 240 / 7.5 \text { OR }(v=) \sqrt{ }\{2 \times 240 / 7.5\}$ $\mathrm{OR}(\mathrm{v}=) \downarrow\{2 \mathrm{KE} / \mathrm{m}\}$

C1

$=8.0 \mathrm{~m} / \mathrm{s}$

A1

(ii)

The kinetic energy of the air drives a generator. State the input power of the air passing through the turbine blades.
input power =

[ 1 ]

(b)

The output current of the generator is 2.0 A . The output potential difference (p.d.) of the generator is 11 V .

[ 2 ]

(i)

Calculate the efficiency of the wind turbine.

[ 2 ]

(efficiency = ) $\mathrm{P}_{\mathrm{o}} / \mathrm{P}_{\mathrm{i}}$ OR (efficiency = ) $\mathrm{P}_{\mathrm{o}} / \mathrm{P}_{\mathrm{i}}$

OR (efficiency = ) $(11 \times 2 / 240) \times 100$

C1

\{efficiency $=(11 \times 2 / 240) \times 100=\} 9.2$ (\%)

A1

[Maximum number: 8]

All the sides of a plastic cube are 8.0 cm long. Fig. 3.1 shows the cube.

Fig. 3.1 (not to scale)

The mass of the cube is 0.44 kg .

(a)

Explain what is meant by mass.

[ 1 ]

(b)

Calculate the density of the plastic from which the cube is made.
density =

[ 2 ]

d=m / V OR in words OR $0.44 / 0.080^{3}$ OR $0.44 / 5.12 \times 10^{-4}$ OR $440 / 8^{3}$ OR 440 / 512 OR $0.44 / 8^{3}$ OR 0.44 / 512

C1

$0.86 \mathrm{~g} / \mathrm{cm}^{3}$ OR $860 \mathrm{~kg} / \mathrm{m}^{3}$ OR $8.6 \times 10^{-4} \mathrm{~kg} / \mathrm{cm}^{3}$

A1

(c)

The density of one type of oil is $850 \mathrm{~kg} / \mathrm{m}^{3}$ .

State and explain whether the cube floats or sinks when placed in a container of this oil.

[ 1 ]

(d)

On the Moon, the weight of the cube is 0.70 N .

[ 4 ]

(i)

Calculate the gravitational field strength on the Moon.
gravitational field strength =

[ 2 ]

$W=m g \operatorname{OR}(g=) W / m \operatorname{OR} 0.70 / 0.44$

C1

$1.6 \mathrm{~N} / \mathrm{kg}$

A1

(ii)

In a laboratory on the Moon, the plastic cube is held stationary, using a clamp, in a beaker of the oil of density $850 \mathrm{~kg} / \mathrm{m}^{3}$ .

The arrangement is shown in Fig. 3.2.

Fig. 3.2

The lower face of the cube is 3.0 cm below the surface of the oil.

Use your answer to (c)(i) to calculate the pressure due to the oil on the lower face of the cube.
pressure =
[Total: 8]

[ 2 ]

( P= ) hdg OR $0.030 \times 850 \times 1.6$

C1

41 Pa

A1

All question bank results loaded

Covered syllabus points

1. Motion, forces and energy question 1

1. Motion, forces and energy question 2

Question (a)

Question (i)

Question (ii)

Question (b)

Question (i)

1. Motion, forces and energy question 3

Question (a)

Question (b)

Question (c)

Question (d)

Question (i)

Question (ii)