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WorksheetsYear 8: Forces
Total questions: 85
Worksheet time: 7hrs 5mins
Which of these is the best way to measure a force?
Using a newtonmeter
Using a thermometer
Using a ruler
Using an ammeter
Forces can be:
Select the correct boxes:
Push
Pull
Twist
Push and Pull only
A force can change the . . .
speed, shape or colour of an object.
speed or direction of an object.
speed, direction or shape of an object.
speed or shape of an object.
What is the unit of force called?
Newton, N
Neutron, N
Metre, m
Centimetre, cm
The _______ of an object depends on the strength of the gravity acting on it.
weight
mass
The name of the force that makes the apple fall to the ground is ___________.
gravity
thrust
magnetism
air resistance
weight
The force created by the car's engine and shown by the arrow is _________.
gravity
weight
thrust
upthrust
air resistance
Friction is a force that acts in an ___________ direction of movement.
opposite
similar
parallel
west
What can we say about the forces on an object that is not moving?
The forces must be balanced
There must only be one force acting on it
It must be very heavy
What is the name for a single force on an object with the same effect as all the forces combined?
resultant
big
total
sum
What is the net force on the block? (The overall force)
5 Newtons up
5 Newtons down
15 Newtons down
15 Newtons up
The _____ of an object is how much matter the object is made up of.
mass
weight
gravity
The resultant force acting
on the balloon is.....
8 N towards the right.
18 N towards the right.
18 N towards the left.
8 N towards the left.
What will cause an object to move?
Unbalanced forces
Applied forces
Balanced forces
What does it mean for an object to be in equilibrium?
Select the INCORRECT answer.
The object is only at rest.
It has no net force acting on it.
The forces acting on the object all cancel out.
The sum of all the forces acting on an object is 0.
What happens to the air resistance on a car as the car goes faster?
Hint: Think about the collision with air particles
It increases
It decreases
It stays the same
What are contact forces?
Forces between touching objects
Forces between similar objects
Forces between objects that do not touch
Which of these involves a contact force?
A skydiver falling through the air
A planet in orbit around a star
Two bar magnets placed next to each other
What is a non-contact force?
Forces between objects that do not touch
Forces between objects that are different to each other
Forces between touching objects
Which of these is a non-contact force?
Weight
Reaction force
Friction
What force is acting UPWARDS on the book?
Reaction force
Friction
Gravity
Thrust
Name force A
Weight
Upthrust
Friction
Reaction force
Name force B
Reaction force
Friction
Gravity
Weight
Name force C
Friction
Reaction force
Weight
Thrust
A liquid exerts a force called _________ on the bottom of an object that's in the liquid.
water resistance
upthrust
lift
What is another name for air/water resistance?
drag
gravity
friction
weight
Which of the following is an example of friction that is helpful?
All are examples that are helpful
Brakes used on a bike
Tires from a car on the road
Tread on the bottom of your shoes
How can friction be reduced?
[Select all correct answers]
Making cross-section of object large
Design of object could be more streamlined
Increasing the roughness of the 2 surfaces coming in contact
Lubrication with wax, grease or oil
Which famous scientist
discovered gravity?
Newton
Galileo
Hawking
Einstein
An elastic material can change shape when ________ is exerted on it.
a force
a moment
an acceleration
If tension is applied, the object may be stretched.
We say the object has been __________.
compressed
extended
twisted
If a compression force is applied, the object may be squashed. We say the object has been __________.
compressed
extended
twisted
A deformation is a change in _________.
speed
shape
direction
Which equation could be used to calculate the extension of an object?
extension = stretched length × original length
extension = stretched length ÷ original length
extension = stretched length + original length
extension = stretched length – original length
What is the extension of the spring?
6 cm
9 cm
3 cm
2 cm
Which materials do not break easily and return to their original shape when forces acting on them are removed?
Elastic
Strong
Plastic
Brittle
Robert Hooke investigates springs by seeing how a load affected their.....
extension
correlation
temperature
energy
Hooke's Law does not apply if....
the spring is stretched too far
the spring is compressed
the spring is not made of steel
masses are used instead of weights
The elastic limit is the point at which ..
the spring does not return to its original size
the spring snaps
there is no more room to attach masses
the spring unravels
The independent variable is force applied to the spring, and the dependent variable is extension of the spring.
Which variable should you record in the left-hand column of the table?
extension of the spring (m)
force applied to the spring (N)
The independent variable is force applied to the spring,
and the dependent variable is extension of the spring.
Which variable should you record in the
right-hand column of the table?
extension of the spring (m)
force applied to the spring (N)
Describe the relationship between the variables for the line in blue.
The extension is directly proportional
to the force applied
The extension increases at
an increasing rate as force is increased
The extension decreases as force is applied
Describe the relationship between the variables for the line in brown.
The extension is directly proportional
to the force applied
The extension increases at
an increasing rate as force is increased
The extension decreases as force is applied
Suggest what material the
line in brown could be for?
spring
rubber band
polythene strip
(plastic bag strip)
Suggest what material the
line in blue could be for?
spring
polythene strip
(plastic bag strip)
rubber band
Suggest what material the
line in green could be for?
spring
rubber band
polythene strip
(plastic bag strip)
The turning effect of a force is called a
moment
momentum
rotation
pivot
The point at which a lever or see-saw balances or rotates.
Pivot
Moment
Momentum
Centre
The turning effect of force can make an object to turn in a ________________ and ___________ direction
Clockwise and Anti-clockwise
Up and Down
Right and Left
Moment (Nm) =
_______ (N) x __________(m)
Force and perpendicular distance
Energy and perpendicular distance
Momentum and perpendicular distance
Speed and time
Calculate the weight of the father!
IF YOU ARE CONFUSED, LOOK BACK IN YOUR BOOK!
600 N
800 N
700 N
500 N
What is the moment acting on the seesaw?
IF YOU ARE CONFUSED, LOOK BACK IN YOUR BOOK!
1.6 Nm anticlockwise
15 Nm anticlockwise
4 Nm clockwise
16 N clockwise
What is the moment produced by the 15 N?
CONVERT cm into m
1.5 Nm (anti-clockwise)
15 Nm (clockwise)
150 Nm (anti-clockwise)
0.15 Nm (clockwise)
When an object is in equilibrium, the sum of clockwise moments is equal to the sum of the anticlockwise moments. Which law states this?
Law of moments
Newton' law of motion
Law of conservation of energy
Law of conservation of momentum
What is moment measured in?
Newton metres (Nm)
Newtons (N)
Kilograms (kg)
What is meant by the centre of mass of an object?
All of the other answers
point at which its mass (seems to) act
point at which gravity (seems to) act
point at which its weight (seems to) act
A fluid is a substance that can flow.
Which states of matter are classed as fluids?
Solid
Liquid
Gas
What causes gas pressure to increase?
[Select 3 options]
Increase in volume
Increased amount of gas particles
Increase in temperature
Decrease in volume
Decrease in temperature
What happens if the weight of an object
in water is equal to the upthrust from the water?
The object sinks.
The object floats.
What happens if the weight of an object in water is greater than the upthrust from the water?
The object sinks
The object floats
What is the name of the resistive force that a solid object experiences as it moves through water?
upthrust
water resistance
thrust
Three balls are placed into the water. Which of these balls will float?
A
B
C
Two balls with the same volume are placed
into the water. Why does ball B sink?
Ball B has a lower density,
so it weighs more than ball A.
Ball B has a greater density,
so it weighs less than ball A.
Ball B has a lower density,
so it ways less than ball A.
Ball B has a greater density,
so it weighs more than ball A.
A fluid exerts pressure on its container.
What direction does fluid pressure act in?
in all directions
up
down
left and right
How does pressure in a fluid
vary with depth?
The greater the depth, the higher the pressure.
The greater the depth, the lower the pressure.
Why is there more water pressure on Cassie than there is on Hannah?
There is more water above Cassie.
Cassie must weigh more than Hannah.
Liquids exert pressure on objects.
The diver at the bottom of the ocean experiences more pressure than the diver closer to the surface. This is because . . .
there is less weight of the water
on top of the diver at the bottom of the ocean.
there is more weight of the water
on top of the diver at the bottom of the ocean.
Where is pressure the greatest
on the dam?
D
A
B
C
Where would you find the largest pressure?
At the bottom of the ocean
At the top of Mt Everest
Close to ground in the MUGA
Hydraulics are based on the concept that:
Fluid is incompressible
Fluid pressure is always unequal
Fluid always takes the path of greatest resistance
Pressure stays the same in the brake fluid
Sort the statements into the correct order
to explain how a hydraulic system works.
1) A force is applied to piston 1, pushing it inwards.
2) Piston 1 puts pressure on the hydraulic fluid.
3) The hydraulic fluid transmits the pressure to piston 2.
4) Piston 2 has a larger surface area than piston 1,
so piston 2 is pushed out with a greater force.
1 → 2 → 3 → 4
1 → 3 → 2 → 4
1 → 4 → 3 → 2
2 → 1 → 3 → 4
What do you notice about the pressure of the hydraulic fluid in this system?
The pressure under piston 1 is greater than
the pressure under piston 2.
The pressure is the same everywhere.
The pressure under piston 2 is greater than the pressure under piston 1.
A hydraulic lift is used to raise a vehicle. A mechanic pushes down on the handle connected to piston 1 with a force of 200 N.
The area of piston 1 is 0.5 m2. What pressure is exerted on the hydraulic fluid by piston 1 in pascals (Pa)?
100 N/m2
200 N/m2
300 N/m2
400 N/m2
The car is sat on piston 2, which has a surface area of 40 m2.
The mechanic pushes down on the handle connected to piston 1, creating a pressure of 400 N/m2 inside the system. What is the force exerted on piston 2 by the hydraulic fluid in newtons (N)?
1600 N
100 N
440 N
Select all true statements
for hydraulic systems.
A hydraulic system uses pressure in a fluid
to multiply the size of the force.
The pressure in the fluid stays the same
A hydraulic system uses pressure in a fluid to
decrease the size of the force
The force is multiplied in a ratio
which is the same as the ratio of the areas.
What would happen if there was a
leak in the hydraulic system?
air would be able to go in which can be squashed so pressure can't be transmitted equally
air would be able to go in which can't be squashed so pressure can be transmitted equally
Edward and his friends are discussing what is meant by pressure. Who is correct?
Edward
William
Jonah
area
mass
time
distance
Look at the pressure triangle.
How do we calculate the force?
p x a
f x p
f ÷ p
f ÷ a
The stress resulting from a force of 50 N exerted over an area of 5 m2 is
10 N/m2
10 N
0.1 N
250 Pa
When the surface area that a force is applied to decreases, the stress __________.
increases
decreases
Calculate which exerts more pressure:
a person in a stiletto heel OR an elephant?
a person in a stiletto heel
an elephant
The variable you change on purpose during an experiment is called the...
Independent variable
Dependent variable
Control variable
The result you measure each time you carry out an experiment is called the...
Dependent variable
Independent variable
Control variable
A variable you keep the same each time you carry out an experiment is called the...
Independent variable
Dependent variable
Control variable
