Questions - Kibworth High School

Kibworth High School Science Revision
Forces
Practice Exam Questions
Level 5-8
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Please can parents sign to confirm that the students completed the questions
and then marked and corrected their work using the mark scheme.
Students may complete the questions either;
a) Under exam conditions
b) Using a revision guide or web based resource such as
bbc bitesize ks3 science.
Completed booklets should be returned to school / with parent signature
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1.
pull of
engine
(a)
A railway engine is being used to try to pull a wagon along a level track.
The wagon’s brakes are on, and the wagon does not move.
(i)
Draw one arrow on the diagram to show the direction of the force
which prevents the wagon from moving.
1 mark
(ii)
Is the force which prevents the wagon from moving greater than,
equal to or less than the pull of the engine?
.............................................................................................................
1 mark
(b)
(i)
When the wagon’s brakes are off, the engine pulls the wagon forwards. A
frictional force also acts on the wagon. In what direction does the frictional
force act?
1 mark
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(ii)
The pull of the engine is 5000 N. When the wagon’s speed is increasing,
how large is the frictional force?
Tick the correct box.
zero
between 0 and 5000 N
5000 N
more than 5000 N
1 mark
(c)
After a while, the wagon travels at a steady speed. The engine is still
pulling with a force of 5000 N.
How large is the frictional force now?
Tick the correct box.
zero
between 0 and 5000 N
5000 N
more than 5000 N
1 mark
Maximum 5 marks
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2.
The drawing below shows an astronaut in space.
He has four small jets attached to his space suit.
These jets produce forces on the astronaut in the directions A, B, C and D.
(a)
The drawing below shows the size and direction of four forces acting
on the astronaut.
In which direction, A, B, C or D, will the astronaut move?
Give the letter.
..............
1 mark
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(b)
The drawing below shows the size and direction of four different
forces acting on the astronaut.
What will happen to the astronaut when the jets produce these four forces?
......................................................................................................................
1 mark
Explain your answer.
......................................................................................................................
......................................................................................................................
1 mark
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(c)
The drawing below shows the size and direction of four different
forces acting on the astronaut.
Draw an arrow on the diagram below to show the direction in which he
will move.
1 mark
maximum 4 marks
3.
Russell investigated the relationship between mass and weight.
He weighed five different masses using a force meter.
His results are shown in the table.
mass (g)
weight (N)
150
1.5
250
2.5
300
3.8
400
4.0
580
5.8
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(a)
He plotted four of his results on a grid as shown below,
(i)
Plot the point for the 150 g mass on the graph.
1 mark
(ii)
Draw a line of best fit.
7.0
6.0
×
5.0
4.0
×
weight
(N)
×
3.0
×
2.0
1.0
0
0
100
200
300
400
500
600
700
800
mass (g)
1 mark
(b)
One of the points Russell plotted does not fit the pattern.
Circle this point on the graph.
1 mark
(c)
Use your graph to predict:
(i)
the mass of an object weighing 6.5 N;
............. g
1 mark
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(ii)
the weight of an object of mass 50 g.
............. N
1 mark
(d)
Give one reason why it is more useful to present the results as a line graph
rather than a table.
.........................................................................................................................
.........................................................................................................................
1 mark
maximum 6 marks
4.
Mary used the apparatus below to test the strength of an electromagnet.
She used the reading on the newton meter to measure the force of the magnet on the
iron disc.
0
N
1
2
3
newton meter
4
5
iron disc
iron core fixed inside coil
power
supply
(a)
100 turns in coil
Explain why the reading on the newton meter increases when a current passes
through the coil.
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........................................................................................................................
........................................................................................................................
........................................................................................................................
........................................................................................................................
2 marks
(b)
When a current passes through the coil, some of the electrical energy is changed
to thermal energy.
What would happen to the coil if the current passing through it was too large?
........................................................................................................................
1 mark
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(c)
Mary made two electromagnets, one with 100 turns of wire in the coil and one
with 200 turns.
She varied the current through the coil of each electromagnet.
She measured the force of each electromagnet on the iron disc.
The graph shows her results.
200 turns
in coil
2.4
2.2
2.0
1.8
1.6
1.4
force on
iron disc 1.2
(N)
1.0
0.8
100 turns
in coil
0.6
0.4
0.2
0
0
0.5
1.0
1.5
2.0
2.5
3.0 3.5
4.0
4.5
5.0
5.5
current through coil (A)
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Write two conclusions that Mary could make from these results.
1. ....................................................................................................................
........................................................................................................................
2. ....................................................................................................................
........................................................................................................................
2 marks
maximum 5 marks
5.
Zena has a model plane attached to a rod as shown below.
The plane is balanced by a sliding counterweight.
10 cm
sliding
counterweight
20 cm
rod
pivot
5N
W
not to scale
(a)
The rod is balanced horizontally.
(i)
Calculate the turning moment produced by the counterweight about the
pivot.
Give the unit.
................................................................................................................
................................................................................................................
2 marks
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(ii)
What is the turning moment produced by the plane about the pivot?
................................................................................................................
1 mark
(iii)
Calculate the weight, W, of the plane.
................................................................................................................
..............................................................................................................N
1 mark
(b)
There is a solar cell on the surface of the model plane.
Zena connected the solar cell to the motor of the plane.
The plane moved in a circle around the pivot.
Part of the path of the plane was in a shadow.
What happened to the speed of the plane as it moved from bright light
into low light in the shadow?
........................................................................................................................
Explain your answer.
........................................................................................................................
........................................................................................................................
1 mark
maximum 5 marks
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6.
The graph shows how the speed of a 0.1 kg mass changes as it falls.
9
8
7
6
speed,
in m/s
5
4
3
2
1
0
0
(a)
0.1
0.2
0.3
0.4 0.5
time, in s
0.6
0.7
0.8
0.9
Read from the graph the speed of the mass at 0.4 s and 0.8 s.
Use your results to work out the average speed of the mass between
0 and 0.4 s and then between 0 and 0.8 s. Give the units.
(i)
final speed at 0.4 s = ............................
average speed between 0 and 0.4 s = ...................................
1 mark
(ii)
final speed at 0.8 s = ............................
average speed between 0 and 0.8 s = ...................................
1 mark
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(b)
Using the average speeds calculated in (a), work out how far the mass falls in:
(i)
0.4 s
.............................................................................................................
1 mark
(ii)
0.8 s
.............................................................................................................
1 mark
(c)
Complete the sentence:
If the mass falls for double the time, it will fall .............................................
times as far
1 mark
Maximum 5 marks
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