SAN ĠORĠ PRECA COLLEGE

Physics Year 9 Tr 2 Half Yearly Examinations 2019 Page 1 of 10

.

Answer all questions.

You are requested to show your working and to write the units where necessary.

The use of a calculator is allowed.

When necessary, take g, acceleration due to gravity, as 10m/s2.

You may find some of these equations useful:

Density m = ρ V

Pressure F = P A P = ρ g h

Moments Moment = F x perpendicular distance

Force and Motion W = m g

Waves T = 1

𝑓

Number 1 2 3 4 5 6 7 8

Maximum

Mark

8 8 8 8 8 15 15 15

Actual

Mark

Total Theory Total Practical Final Mark

Actual Mark

Maximum Mark 85 15 100

SAN ĠORĠ PRECA COLLEGE

Ħ A M R U N S E C O N D A R Y S C H O O L

Subtitle Text

HALF-YEARLY EXAMINATIONS 2019

YEAR:9 SUBJECT: Physics TIME: 1½ hours

STUDENT‘S PAPER NAME & SURNAME: __________________ CLASS: _______ INDEX NO: ____

Level

Tr 2


Section A: This section carries 40 marks.

1. This question is about Measurements.

a) Fill in the following table: (4)

Term Symbol SI unit

Mass

t

Force

kg/m3

b) Write in standard form:

i) 54,200 = _____________________ (1)

ii) 0.0000687 = ___________________ (1)

c) Convert 30 minutes to seconds

_________________________________________________________________________(1)

d) Change 56g to kg

_________________________________________________________________________(1)

2. This question is about density.

a) Give 3 steps how to find the volume of a door key stating the instrument used to measure.

________________________________________________________________________

________________________________________________________________________

________________________________________________________________________

_____________________________________________________________________ (3)

b) Which instrument must be used to find the mass of the key? (1)

___________________________________________________________________________


c) If the mass of the key is found to be 78g and its volume was found to be 10cm3, calculate

the density of the key. (1)

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

d) Choose the material of this key from the following table: _____________________ (1)

Material Density (kg/m3)

Aluminium 2712

Steel 7850

Nickel 8908

Water 1000

e) Would this key float or sink in water? Why?

____________________________________________________________________ (1)

f) Name the instrument used to measure the thickness of this key. (1)

___________________________________________________________________________

3. This question is about Forces.

a) Jo, Daniel and Helen are pulling a metal ring. Jo pulls

with a force of 100N in one direction and Daniel pulls

with a force of 140N in the opposite direction. If the

ring does not move, what force does Helen exert if she

pulls in the same direction as Jo? Draw arrows on the

diagram to help you. (2)

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________


b) Match the following two columns by writing the matching number in the third column.

1 Weight The pull of a string/spring

2 Friction The force of gravity due to the pull of the earth

3 Air resistance The contact force which opposes the Action

4 Tension The force which opposes motion when flying

5 Upthrust The force which resists motion when two surfaces

move against each other

6 Reaction The upward push of an object immersed in a

liquid

(6)

4. This question is about Moments.

a) What is meant by the moment of a force? (1)

___________________________________________________________________________

b) The see-saw in the diagram below is balanced when Shaun of mass 32kg sits at A, Tom of

mass 54kg sits at B and Harry sits at C.

i) Find Shaun’s weight. (1)

_________________________________________________________________

ii) Find Shaun’s moment about O. (1)

_________________________________________________________________

iii) Find Tom’s weight. (1)

_________________________________________________________________

iv) Find Tom’s Moment about O. (1)

_________________________________________________________________

v) Find Harry’s weight. (2)

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

A B

3m

C

1 m

O

3m


vi) What is the total upward force on the central support of the see-saw? (1)

_________________________________________________________________

5. This question is about Pressure.

a) Fill in:

i) In fluids (liquids and gases), pressure acts in ______ directions and pressure

________________ as the depth increases. (2)

ii) Atmospheric pressure can be measured by a mercury ___________________.

b) The height of the Mercury column for standard atmospheric pressure is 760mm. Calculate

the atmospheric pressure, in Pascal, if Mercury has a density of 13,534 kg/m3.

___________________________________________________________________________

___________________________________________________________________________

_________________________________________________________________________(2)

c) i) A gas is in a closed container. As the temperature increases, what happens to the gas

pressure in the container? (1)

___________________________________________________________________________

ii) The same amount of gas is transferred to a smaller closed container at a constant

temperature, what happens to the gas pressure inside the container? (1)

___________________________________________________________________________

d) The picture shows a rubber sucker used to attach a soft toy

to a window. Draw arrows on the picture and explain why it

becomes attached to the window. (2)

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

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Section B: This section carries 45 marks.

6. This question is about Pressure.

a. Pressure is defined as the _________________ per unit _______________.

The unit used for Pressure is the ________________. (2)

b. Describe an experiment of how we can calculate the pressure exerted by both of our feet onto

the ground when bare footed. Your description should include:

i. The Apparatus required

_______________________________________________________ (2)

ii. A brief method

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

__________________________________________________________________(3)

iii. To calculate the pressure exerted by both of our feet, the equation to be used is given

as:

𝑃 =

c. Kate uses a pair of roller blades to go roller skating on Sunday afternoon.

Each roller blade has four small wheels as shown in the picture. While

roller skating, the area of contact with the ground of one wheel is

0.0002𝑚2.

i. Calculate the total area of contact with the ground when she stands

on both feet upright with all eight wheels touching the ground.

________________________________________________________________________

________________________________________________________________________

______________________________________________________________________(2)

(1)


ii. If Kate’s weight is 350N, calculate the pressure that she exerts on the ground when she

stands upright with all eight wheels touching the ground.

________________________________________________________________________

________________________________________________________________________

______________________________________________________________________(3)

iii. In this question you need to underline the correct answer.

While roller skating, Kate can balance herself on just one foot. When balancing on one

foot, the pressure exerted is (increased / decreased). This is because the pressure is

inversely proportional to the (force / area of contact). (2)

7. This question is about centre of gravity and stability.

a) Continue the following statement by using a word or number from the box below:

All objects can be balanced on a point called the centre of gravity. When balanced, all the __________

of the object seems to be concentrated at this point. A uniform metre ruler, will have this point on its

___ cm mark. (2)

b) Draw a well labelled diagram of the apparatus set up to find the centre of gravity of an irregularly

shaped lamina. (3)

time, 50, 100, weight


c) Below are the steps taken to find the centre of gravity of an irregularly shaped lamina. These steps

are not in order. List them in order by placing the numbers from 1 to 6 next to each step. The first one

has been done for you. (2)

d) Mark the centre of gravity of the shapes below. Show all your work. (2)

e) Continue the following statement by using a word or number from the box below:

An object is ________________ if when tilted it goes back to its original _______________________.

The stability of an object depends on _____ factors. The bigger the base __________, the more stable

the object is. The other factor depends on the centre of gravity; the _____________ it is, the more

stable the object is. (5)

f) A cereal box is rotated in 3 different positions as shown below, in positions A, B and C. Which position

is the most stable and which other position is the least stable? (1)

Most stable: ____; Least stable: ____

A straight line passing through these marks is drawn using a ruler.

The object is hung from a clamp together with a plumb-line and left to stop swinging.

1 Three or more holes are made in the irregularly shaped object.

The point at which the three lines intersect is the centre of gravity of the object.

The steps are repeated for at least two more positions.

Two marks along the plumb-line are marked.

A B

C

higher, 2, top, stable, area, unstable, 6, position, lower


8. This question is about Hooke’s law.

Keith hangs a helical spring to a retort stand as shown in the diagram. He starts to add the

masses gradually and the spring extends accordingly.

a) Underline the correct word.

Hooke’s law states that the (length, extension, ruler) is directly proportional to the (force, mass,

gravity) provided elastic limit is not exceeded. (2)

b) The table below represents the results of Keith’s experiment. Plot a graph of extension/cm on the

y-axis against Load/N on the x-axis. (5)

c) Was the elastic limit exceeded? Explain your answer from the graph. (2)

___________________________________________________________________________

d) Fill in the blanks using the correct word. Not each word needs to be used, and each word can be

used more than once. (6)

best proportional force obeys

inversely straight obeyed line extension

curve directly

From this experiment, one can conclude that Hooke’s law is __________________. This can be shown

from the _______________ _________________ _______________. This shows that the force and

extension are ____________________ __________________________.

Extension/cm 0 7 15 23 30 38

Force/N 0 2 4 6 8 10


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