2

1 A student uses a ruler to measure the length of a piece of wire, as shown in Fig. 1.1.

wire

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
cm

Fig. 1.1 (not to scale)

(a) Use the ruler in Fig. 1.1 to determine the length of the piece of wire.

length of wire = .................................................... cm [2]

(b) The student folds the piece of wire and measures its mass.
apparatus
(i) State the name of an instrument the student can use to measure mass.
balance
..................................................................................................................................... [1]

(ii) The student determines the volume of the wire.

He uses a measuring cylinder part‑filled with water and places the wire in it, as shown in
Fig. 1.2.

folded wire

cm3 cm3
50 50

40 40

30 30

20 20 water
water
10 10
folded wire

Fig. 1.2

Determine the volume of the wire by using information in Fig. 1.2.

volume of wire = ...................................................cm3 [2]

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(c) The student measures the mass and the volume of a piece of metal.
The mass of the piece of metal is 93.6 g and its volume is 12 cm3.

Calculate the density of the metal.

density of metal = ...............................................g / cm3 [3]

[Total: 8]

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2 A slope is made by resting one end of a plank of wood on a block, as shown in Fig. 2.1.

plank trolley

block of wood

Fig. 2.1

Two students each use a digital stop‑watch to measure the time for a small trolley to roll down the
full length of the slope.

Fig. 2.2 shows the times on the stop‑watches.

min sec 1
100

student 1 00 : 06 14 time = ......................... s

min sec 1
100

student 2 00 : 06 28 time = ......................... s

Fig. 2.2

(a) (i) On the line next to each stop‑watch, write the time it shows. [1]

(ii) Calculate the average time for the trolley to roll down the slope.

average time = ....................................................... s [2]

(iii) The students want the same trolley to take more time to roll down the plank.

Suggest how the students alter the arrangement in Fig. 2.1.

.....................................................................................................................................
use the shorter of block of wood [1]
note: the less slanted surface, the longer time taken for the trolly to move.

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(b) A different trolley travels 1.2 m down the slope in a time of 7.8 s.

Calculate the average speed of the trolley.

average speed = .................................................. m / s [3]

(c) The trolley travels down a different slope. Fig. 2.3 shows the speed–time graph.

1.6

1.4
speed
m / s 1.2

1.0

0.8

0.6

0.4

0.2

0
0 1.0 2.0 3.0 4.0
time / s

Fig. 2.3

Calculate the distance travelled by the trolley between time = 0 and time = 4.0 s.
distance travelled = the area under the speed - time graph

distance travelled = ...................................................... m [3]

[Total: 10]

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3 (a) A student determines the centre of mass of a piece of card. Fig. 3.1 shows the equipment the
student uses.

pin
cork
A

stand

card

ruler

C
cotton thread

weight

Fig. 3.1

Describe how the student determines the centre of mass of the card using the equipment in
Fig. 3.1.
hang the triangle from the corner A and draw lines alongside the thread
...................................................................................................................................................

...................................................................................................................................................
by using the ruler and pen
repeat it by hanging the triangle from other corner B and C
...................................................................................................................................................
mark the intersection of the lines as a centre of mass of the card
...................................................................................................................................................

...................................................................................................................................................

............................................................................................................................................. [3]

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(b) Another card is pivoted at point P. The weight of the card is 1.4 N and acts through a point
20 cm from P.

Fig. 3.2 shows the arrangement.

card

P 20 cm

pivot
1.4 N

Fig. 3.2

Calculate the moment of the weight of the card about point P.

moment of weight = ................................................. N cm [3]

[Total: 6]

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1 A cyclist travels to a friend’s house.

Fig. 1.1 shows the distance–time graph of the journey.

1000
E
distance / m

800
D

600

400
B C

200

A
0
0 100 200 300 400 500
time / s

Fig. 1.1

(a) Determine the distance travelled by the cyclist between points C and E.

distance travelled = .................................................... m [2]

at rest
(b) Describe the motion, if any, of the cyclist between points B and C. ................................... [1]

(c) State the section, AB, BC, CD or DE, of the graph in which the speed of the cyclist is the
fastest. Give a reason for your answer.
the most slanted line
section of graph ....................................................
it has the greatest gradient
reason ................................................................................................................................. [2]

(d) Calculate the average speed of the cyclist between points A and E. Include the unit in your
answer.

average speed = ................................ unit ................ [4]

[Total: 9]
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2 (a) A coin collector has 19 identical coins, as shown in Fig. 2.1.

Fig. 2.1

Fig. 2.2 shows one of the coins in the coin collector’s hand.

Fig. 2.2

The coin collector wants to check the thickness of one coin. She has a 30 cm ruler.

Describe how she can use the 30 cm ruler to determine the thickness of one coin accurately.

You may include a diagram if you wish.

arrange the coins vertically or stack the coins vertically

...................................................................................................................................................

find the length of the 19 coins

...................................................................................................................................................

then divided by 19 to find the thickness pf one coin

...................................................................................................................................................

............................................................................................................................................. [3]

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(b) The coin collector finds another coin. She thinks this coin is made of gold.

She performs an experiment to find the coin’s density.

She obtains the following results:

mass of coin = 52.5 g

volume of coin = 5.4 cm3

(i) Show that the density of this coin is about 10 g / cm3.

[3]

(ii) The density of liquid mercury is 13.6 g / cm3. State and explain whether the coin in (b)(i)
floats on liquid mercury.
coin floats because its density is lower than liquid mercury
...........................................................................................................................................

..................................................................................................................................... [1]

[Total: 7]

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3 Fig. 3.1 shows the vertical forces acting on a toy rocket as it leaves the ground.

upward force = 70 N

smooth surface

weight of rocket = 15 N

Fig. 3.1

(a) Calculate the size of the resultant vertical force on the rocket.

resultant force = .................................................... N [2]

(b) Explain why the top of the rocket is pointed and has a smooth surface.
a smooth surface to reduce the friction
...................................................................................................................................................
and pointed top to reduce air resistance force
............................................................................................................................................. [2]

[Total: 4]

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4 (a) A teacher wants to measure the mass of a block of metal. She also wants to measure the
length, width and height of the block.

Fig. 4.1 shows the block of metal.

length width

height

Fig. 4.1

Complete each sentence using a word from the list.

balance barometer protractor ruler voltmeter

(i) balance
To find the mass of the metal block, the teacher uses a ............................................. [1]

(ii) ruler
To measure the length, width and height of the metal block, she uses a .................... [1]

(b) The mass of the block is 5000 g.

Calculate the weight of the block.

weight = .................................................... N [3]

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(c) Fig. 4.2 shows another block of metal on a solid surface.

20 cm 12 cm
solid surface
2.0 cm

Fig. 4.2 (not to scale)

(i) Calculate the area of the block of metal in contact with the solid surface.

area = ................................................. cm2 [1]

(ii) The weight of the block of metal in Fig. 4.2 is 60 N.

Calculate the pressure of the block of metal on the solid surface.

pressure = ............................................ N / cm2 [3]

[Total: 9]

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8 Fig. 8.1 shows a simplified diagram of a geothermal power station.

kinetic energy stored by rotating
turbine generate the generator to
moving steam exert force to produce electricity
rotate the turbine
turbine generator

steam
cooling
tower

steam cold
water
stored kinetic energy

Fig. 8.1

(a) (i) geothermal

State the energy source for a geothermal power station. ........................................... [1]

(ii) Complete the sentence about useful energy transfer in the power station.

kinetic
The generator converts ................................... energy into ...................................
electrical energy.
[2]

(b) (i) State two advantages of a geothermal power station compared to a coal-fired power
station.
less carbon dioxide emissions
1 ........................................................................................................................................
renewable energy
2 ........................................................................................................................................
[2]

(ii) State one disadvantage of using geothermal energy rather than coal in a power station.

less energy is produced

..................................................................................................................................... [1]

[Total: 6]

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1 Fig. 1.1 shows a plant pot falling from an upstairs balcony. The plant pot has a constant acceleration
as it falls.

balcony

plant pot

ground level

Fig. 1.1

(a) State the cause of the acceleration.

.............................................................................................................................................
gravitational force [1]

(b) Fig. 1.2 shows the speed–time graph for the falling plant pot. The plant pot hits the ground at
time = 1.8 s.

16
speed
m/s

12

0
0 0.4 0.8 1.2 1.6 2.0
time / s

Fig. 1.2

Determine the height of the balcony above the ground using the information shown in Fig. 1.2.

height = ...................................................... m [3]

[Total: 4]

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2 Fig. 2.1 shows a pea plant. One of the pods is open, showing the peas inside.

pea plant

pea pods peas

Fig. 2.1

(a) A food scientist needs to find the average diameter of a pea.

She places 14 peas against a ruler, as shown in Fig. 2.2.

Fig. 2.2

Use information from Fig. 2.2 to determine the average diameter of one pea.

average diameter of one pea = .................................................... cm [3]

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(b) The food scientist needs to find the average density of some peas.

She uses the following values:

mass of peas = 183 g

volume of peas = 250 cm3.

Calculate the average density of these peas.

average density = ...............................................g / cm3 [3]

(c) A different variety of pea has a density of 0.89 g / cm3. One pea of this variety is placed in salt
water. The density of the salt water is 1.02 g / cm3.

State whether this pea floats or sinks in the salt water. Give a reason for your answer.

answer ...............................................................
density of a pea is smaller than density of salt water
reason .......................................................................................................................................
[1]

[Total: 7]

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3 Fig. 3.1 shows the horizontal forces acting on a skateboarder.

backward force = 60 N forward force = 100 N

skateboarder
skateboard

Fig. 3.1

(a) Calculate the resultant force acting on the skateboarder.

resultant force = ............................................................ N

direction = ...............................................................
[2]

(b) Describe the effect of the resultant force in (a) on the motion of the skateboarder.
the skateboarder moves
............................................................................................................................................. [1]

(c) The skateboarder is moving along a horizontal path.

The backward force is 100 N. The forward force is 100 N.

Describe the motion of the skateboarder.

the skateboarder does not move

............................................................................................................................................. [1]

[Total: 4]

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4 (a) (i) State the principle of conservation of energy.

energy cannot be created or destroyed, but can be converted

...........................................................................................................................................

..................................................................................................................................... [1]

(ii) Fig. 4.1 shows a type of light bulb. Energy changes occur when electrical energy is
supplied to the light bulb, as shown in Fig. 4.1.

useful output = 50 J of light

wasted energy

total input = 500 J of electrical energy

Fig. 4.1

Calculate the wasted energy when the total input energy is 500 J.
Use information from Fig. 4.1.

wasted energy = ....................................................... J [2]

(iii) Describe the effect of the wasted energy on the air surrounding the light bulb.

the air becomes warmer

..................................................................................................................................... [1]

(b) Table 4.1 lists situations in which energy is stored.

Complete Table 4.1 by naming the form of energy stored in each situation.

Table 4.1

situation form of energy stored

battery in a mobile phone chemical
coal in the ground chemical
a rotating turbine kinetic
water stored behind a hydroelectric dam gravitational potential
[4]

[Total: 8]

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6 (a) In Fig. 6.1, the circles represent molecules. The diagram shows the arrangement of the
molecules in a liquid.
gas particles exert force on the wall of container

solid liquid gas

Fig. 6.1

(i) Show the arrangement of the molecules in a solid.

Draw a diagram in the box above the word ‘solid’ in Fig. 6.1. Draw at least 10 molecules.
[2]

(ii) Show the arrangement of the molecules in a gas.

Draw a diagram in the box above the word ‘gas’ in Fig. 6.1. Draw at least 10 molecules.
[2]

(iii) State the name of the process by which a solid changes into a liquid.

melting
..................................................................................................................................... [1]

(iv) State the name of the process by which a gas changes into a liquid.

condensing
..................................................................................................................................... [1]

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