Physics – Year 9 – Track 2 – 2018 Page 1 of 11

DEPARTMENT FOR CURRICULUM,

RESEARCH, INNOVATION AND LIFELONG LEARNING

Directorate for Learning and Assessment Programmes

Educational Assessment Unit

Annual Examinations for Secondary Schools 2018

YEAR 9 PHYSICS TIME: 2 hours

Name: _______________________________ Class: _________________

INFORMATION FOR CANDIDATES

• Where necessary take acceleration due to gravity ‘g’ to be 10 m/s2.

• The use of a calculator is allowed.

• The number of marks for each question is given in brackets [ ] at the end of each question.

• You may find these equations useful.

Density m = ρ V

Pressure P = ρ g h F = P A

Forces W = m g

Moments Moment = F × perpendicular distance

Energy P. E. = m g h K. E. =

1

2mv2 Work Done = F s

Work Done = Energy Converted E = P t

Heat ΔQ = m c Δθ

INSTRUCTIONS TO CANDIDATES

• Use blue or black ink. Pencil should be used for

diagrams only.

• Read each question carefully and make sure that you

know what you have to do before writing your

answer.

• Answer ALL questions.

• All working must be shown.

For Examiner’s Use Only

Question Max Mark

1 8

2 8

3 8

4 8

5 8

6 15

7 15

8 15

Written 85

Practical 15

Total 100

This document consists of 11 printed pages.

Track 2

Page 2 of 11 Physics – Year 9 – Track 2 – 2018

SECTION A

Each question carries 8 marks. This section carries 40 marks of the total marks for this paper.

1. Figure 1 below shows some of the forces acting on a car of 850 kg.

a) Label the Forces FA and F

B shown in Figure 1. [2]

b) On the same diagram draw the weight of the car. [1]

c) Mention TWO differences between mass and weight.

___________________________________________________________________________

________________________________________________________________________ [2]

d) Calculate the weight of the car.

__________________________________________________________________________

________________________________________________________________________ [2]

e) Name the upward force that the ground exerts on the car.

________________________________________________________________________ [1]

2. Figure 2 shows a measuring cylinder that contains a certain volume of liquid.

Amy takes the following measurements:

Mass of the empty measuring cylinder = 205.0 g

Mass of the cylinder and liquid = 240.2 g

a) Use the information provided to find the mass of the liquid.

__________________________________________________[1]

b) Calculate the density of the liquid.

___________________________________________________________________________

___________________________________________________________________________

________________________________________________________________________ [3]

FA = F

B =

Figure 1

cm3

50

40

30

20

10

Figure 2

Physics – Year 9 – Track 2 – 2018 Page 3 of 11

c) The table below shows the density of different liquids.

Liquid Water Alcohol Honey Olive Oil

Density (g/cm3) 1.00 0.79 1.42 0.92

i) Identify the liquid used by Amy in her experiment. Explain your choice.

_________________________________________________________________________

______________________________________________________________________ [2]

ii) Using the words below, write a sentence to explain why honey is denser than water.

honey particles packed

_________________________________________________________________________

______________________________________________________________________ [2]

3. An athlete is running a race. Her body temperature rises and she starts sweating. As the sweat

evaporates, her body cools down.

a) In terms of molecules, explain how the process of evaporation helps her body to keep cool.

___________________________________________________________________________

___________________________________________________________________________

________________________________________________________________________ [3]

b) Underline the correct answer.

At the end of the race the athlete is told to wear a tracksuit jacket. This helps the rate of

evaporation to (increase, stays the same, decrease) and the body cools down more (slowly,

quickly). [2]

c) Mention ONE other situation where evaporation takes place.

________________________________________________________________________ [1]

d) Mention TWO factors that help to increase evaporation.

___________________________________________________________________________

________________________________________________________________________ [2]

Page 4 of 11 Physics – Year 9 – Track 2 – 2018

4. The Hubble space telescope (marked H in Figure 3)

was launched in orbit in 1990 and is still orbiting

the Earth. The discoveries made while using this

telescope have transformed the way how scientists

look at the Universe.

a) Add to Figure 3 an arrow that represents the force keeping the Hubble space telescope in orbit

around the Earth. [1]

b) How would the size of this force change if the telescope is moved further away from the Earth?

________________________________________________________________________ [1]

c) The graph shows that the speed of

the telescope may vary as it orbits

at different distances from the

Earth.

i) The Hubble space telescope

orbits at a distance of 600 km

away from the Earth. Use the

graph to determine its speed at

this orbit.

_______________________[1]

ii) The telescope has a mass of 11 000 kg. Calculate the kinetic energy of the telescope in

orbit.

_________________________________________________________________________

______________________________________________________________________ [2]

iii) Underline the correct answer.

While the telescope is in orbit, its kinetic energy (increases, stays the same, decreases).

[1]

d) Scientists still have many unanswered questions about our Universe. List TWO of these

questions.

_____________________________________________________________________________

___________________________________________________________________________ [2]

H

Figure 3

6800

7000

7200

7400

7600

7800

8000

0 200 400 600 800 1000 1200 1400 1600 1800

Speed [m/s]

Distance from the Earth's Surface [km]

Physics – Year 9 – Track 2 – 2018 Page 5 of 11

5. Figure 4a shows a side view of a laptop computer.

Ben opens the laptop cover with an upward force of 5 N. This force is applied 0.20 m from the

pivot as shown.

a) i) Fill in the missing spaces in the table below.

Quantity Symbol Units

Moment

Force F N

Distance d

[3]

ii) Calculate the moment of the force that opens the laptop.

________________________________________________________________________

____________________________________________________________________ [2]

iii) On Figure 4a daw the weight of the laptop cover. Label its distance from the pivot

carefully. [1]

b) Ben discovers that 5 N is the minimum upward force needed to open the laptop. Then he

applies a downward force F to close the laptop as shown in Figure 4b.

Explain why the minimum force needed to close the laptop is likely to be smaller than 5 N.

________________________________________________________________________________

_____________________________________________________________________________[2]

0.20 m

5 N Pivot

Figure 4a

F

0.20 m Pivot

Figure 4b

Page 6 of 11 Physics – Year 9 – Track 2 – 2018

SECTION B

Each question carries 15 marks. This section carries 45 marks of the total marks for this paper.

6. Charlene and Timothy have designed a car windscreen washer system as shown in Figure 5a.

a) When a force is produced on the plunger, water is squirted on the windscreen.

i) A force of 5 N acts on the piston which has an area of 0.0001 m2. Calculate the pressure

produced by the piston.

_____________________________________________________________________________

__________________________________________________________________________ [2]

ii) Underline the correct answer.

Since pressure acts in (all, no) directions, the pressure of water at the outlet valve

(is equal to, smaller than) the pressure at the piston. [2]

iii) Calculate the force acting on the metal ball at the outlet valve, given that this has an area

of 0.0025 m2.

_____________________________________________________________________________

__________________________________________________________________________ [2]

Figure 5a

Metal ball

Cylinder

Outlet Valve

(Area = 0.0025 m2)

Piston

(Area = 0.0001 m2)

Inlet Valve

Inlet

Valve

Metal ball

Force = 5 N

Plunger

Physics – Year 9 – Track 2 – 2018 Page 7 of 11

b) Charlene always adds some liquid soap in the water bottle (Figure 5b). The liquid soap stays

at the bottom of the water bottle.

i) The atmospheric pressure is 101 kPa. Express this value in Pa.

___________________________________________________________________________ [1]

ii) Draw TWO arrows to show the atmospheric pressure acting at the surface of the water.

[1]

iii) Find the pressure due to the water ONLY acting at point A, which is 0.15 m below the

surface, given that the density of water is 1000 kg/m3.

_____________________________________________________________________________

___________________________________________________________________________ [2]

iv) The depth of the liquid soap is 0.05 m. Calculate the pressure due to the liquid soap ONLY,

given that the density of liquid soap is 1060 kg/m3.

_____________________________________________________________________________

___________________________________________________________________________ [2]

v) Find the TOTAL pressure at the bottom of the water bottle due to the air, soap and water.

___________________________________________________________________________ [1]

c) Underline the correct answer.

Particles in liquids have more freedom than particles in (gases, solids), which is why a liquid

can flow freely. Particles in gases move (faster, slower) than particles in liquids. [2]

Water

Liquid

Soap B

A

0.15 m

0.05 m

Figure 5b

Page 8 of 11 Physics – Year 9 – Track 2 – 2018

7. Figure 6 shows a cross section of a solar water heater.

a) Explain why the absorber plate is painted black.

__________________________________________

_______________________________________ [1]

b) Explain why the pipes are made of copper.

__________________________________________

_______________________________________ [1]

c) The insulating material helps to reduce heat losses. Mention one suitable material that could

be used as an insulating material. _____________________________________________ [1]

d) Underline the correct answer.

The glass sheet of the solar panel creates a (greenhouse, cooling) effect.

Radiation can pass through the cover and is mostly trapped inside.

So the temperature inside the solar water heater (increases, decreases). [2]

e) On a particular day, 30 kg of water is pumped through the pipes of the solar water heater. The

temperature of water rises from 15°C to 40°C.

i) Calculate the change in temperature Δθ. ____________________________________ [1]

ii) The specific heat capacity of water is 4200 J/kg°C. Calculate the heat energy Q transferred

to the 30 kg of water.

_____________________________________________________________________________

___________________________________________________________________________ [2]

f) A student wanted to investigate the cooling process of water in the storage tank of the solar

water heater. To carry out his investigation he poured some hot water in a beaker and recorded

its temperature at 30 s intervals. The results are listed in the table below.

Time/s 0 30 60 90 120 150

Temperature/°C 85 72 64 60 57 56

i) On the graph paper provided, plot a graph of Temperature/oC on the y-axis against Time/s

on the x-axis. Draw the best curve through your points. [5]

ii) Underline the correct answer.

The water cooled down (faster, slower) when the temperature was lower.

After three (minutes, hours) the water cooled down to room temperature. [2]

Glass sheet

Black

absorber plate

Black copper

pipe

Sunlight

Insulating

material Water flowing

Insulating material

Figure 6

Physics – Year 9 – Track 2 – 2018 Page 9 of 11

30

35

40

45

50

55

60

65

70

75

80

85

90

0 20 40 60 80 100 120 140 160

Page 10 of 11 Physics – Year 9 – Track 2 – 2018

8. Jasmine decides to investigate how the efficiency of a motor depends on the weight being lifted.

She uses the apparatus shown in Figure 7 below.

a) The energy provided by the power supply enables the motor to lift different weights. Use the

energy flow diagram below to describe how energy changes in this situation. [3]

b) Jasmine adds different weights and each time she measures the energy input to the motor using

the joulemeter. Her results are shown in the table below.

Weight / N

(Force)

Distance

moved / m

Useful energy output / J

(Work done by motor)

Total energy input / J

(Shown on joulemeter)

Efficiency /

%

2 0.8 1.6 16 10

3 0.8 30

4 0.8 53

5 0.8 100

Power supply

Joulemeter

Motor

Weight

Figure 7

____________________

____________________

In the power supply

____________________

____________________

In the motor

____________________

____________________

In the weight at the top

Physics – Year 9 – Track 2 – 2018 Page 11 of 11

i) Fill in the third column of the table as follows: Calculate the work done by the motor each

time a weight is lifted 0.8 m. Show your working below.

_____________________________________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

___________________________________________________________________________ [3]

ii) Underline the correct answer.

The energy input shown on the joulemeter is not equal to the useful energy output since

energy also changes to (heat, light) and (electrical, sound) energy in the motor. [2]

iii) Fill in the fifth column of the table as follows: Use the results found in question b) (i) to

calculate the efficiency of the motor for each weight lifted. Write the answers in the table.

_____________________________________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

__________________________________________________________________________ [3]

iv) Jasmine thinks that the motor is more efficient when lifting SMALLER weights. Is Jasmine

correct? Give a reason for your answer.

_____________________________________________________________________________

_____________________________________________________________________________

___________________________________________________________________________ [2]

c) Jasmine tries to look at the time it takes for the motor to lift the weights. Calculate the power

developed by the motor given that the time to lift the weights is 3.2 s and the energy is 1.6 J.

_____________________________________________________________________________

___________________________________________________________________________[2]

End of Examination