MCQ on Force and Pressure Class 8
Choose the correct answer.
Question 1.
A push or a pull is called
A) friction
B) pressure
C) force
D) none of these
Answer:
C) force
Question 2.
Hoisting a flag is related to
A) push
B) pull
C) push and pull both
D) pressure
Answer:
B) pull
Question 3.
A person is pulling water from well. Which type of force it is ?
A) Muscular force
B) Magnetic force
C) Friction force
D) Electrostatic force
Answer:
A) Muscular force
Question 4.
Let the forces F1 and F2 act on the table in opposite direction, F1 > F2
then Fnet = …………..
net
A) F1 + F2
B) F1 – F2
C) 0
D) 2F2 – F1
Answer:
B) F1 – F2
Question 5.
Which one of the following is an example for non contact force?
A) Pushing a table
B) Pressing toothpaste
C) Deflection of needle in compass
D) Lifting a bag
Answer:
C) Deflection of needle in compass
Question 6.
What is the direction of frictional force ?
A) Opposite to the motion of object
B) Upward
C) Downward
D) In the direction of force
Answer:
A) Opposite to the motion of object
Question 7.
When the object is freely falling what is the force acting on it?
A) Normal force
B) Frictional force
C) Gravitational force
D) None
Answer:
C) Gravitational force
Question 8.
A rubbed balloon attracts pieces of paper due to
A) Frictional force
B) Magnetic force
C) Electrostatic force
D) Gravitational force
Answer:
C) Electrostatic force
Question 9.
Force has
A) Direction
B) Magnitude only
C) Both A and B
D) None
Answer:
C) Both A and B
Question 10.
When the force acting on an object are equal in opposite direction, the object remains
A) Moves forward
B) backward
C) upwards
D) stationary
Answer:
D) stationary
Question 11.
An example for non – contact force is ___________
A) Normal force
B) Frictional
C) Muscular
D) Gravitational
Answer:
D) Gravitational
Question 12.
A force cannot change the ___________
A) speed of an object
B) mass
C) shape of object
D) direction of moving object
Answer:
B) mass
Question 13.
The force acting on unit area of a surface is called __________
A) momentum
B) density
C) pressure
D) velocity
Answer:
C) pressure
Question 14.
Pressure ________
A) Force
B) Force × Area
C) Area / Force
D) Force / Area
Answer:
D) Force / Area
Question 15.
The force of attraction between any two objects having mass is
A) frictional
B) muscular
C) gravitational
D) magnetic
Answer:
C) gravitational
Question 16.
If the area is less, then the value of pressure is ___________
A) less
B) more
C) does not change
D) none of these
Answer:
B) more
Question 17.
The direction of friction and the direction of motion are always _________
A) same
B) opposite
C) A or B
D) we can’t say
Answer:
B) opposite
Question 18.
When a balloon rubbed with plastic paper and brought near the pieces of paper. What is your observation ?
A) Balloon attracts pieces of paper
B) Balloon does not attract pieces of paper
C) Balloon is blow out
D) Increases size of the balloon
Answer:
A) Balloon attracts pieces of paper
Question 19.
P : Force has magnitude as well as direction.
Q : State of motion of a body can’t be changed by net force.
A) P False, Q True
B) P and Q are true
C) P and Q are false
D) P true, Q false
Answer:
D) P true, Q false
Question 20.
Unit of pressure is __________
A) N
B) N / meter
C) N/meter2
D) N. meter
Answer:
C) N/meter2
Question 21.
Which of the following forces are field forces ?
1) Magnetic forces
2) Electrostatic forces
3) Gravitational forces
A) Only 1
B) Only 2
C) Only 1 and 2
D) All 1, 2 and 3
Answer:
D) All 1, 2 and 3
Question 22.
Assertion (A) : A boy pushes the tyre again and again with a stick to increase its speed.
Reason (R) : If the net force acts in the direction of motion, the speed of an object moving with constant speed also increase.
A) A and R are true, R supports A
B) A and R are true, R doesn’t support A
C) A and R are false
D) A is true and R is false
Answer:
A) A and R are true, R supports A
Question 23.
Choose correct matching option.
Group A | Group B |
1) Gravitational force | a) Horse pulling a cart |
2) Frictional force | b) Iron nails attracted |
3) Electrostatic force | c) Fruit falling from a tree |
4) Magnetic force | d) Heat is generated |
5) Muscular force | e) Bits of paper are raised |
A) 1 – c, 2 – d, 3 – e, 4 – b, 5 – a
B) 1 – a, 2 – b, 3 – c, 4 – d, 5 – e
C) 1 – e, 2 – c, 3 – d, 4 – a, 5 – b
D) 1 – e, 2 – d, 3 – a, 4 – b, 5 – c
Answer:
A) 1 – c, 2 – d, 3 – e, 4 – b, 5 – a
Group A | Group B |
1) Gravitational force | c) Fruit falling from a tree |
2) Frictional force | d) Heat is generated |
3) Electrostatic force | e) Bits of paper are raised |
4) Magnetic force | b) Iron nails attracted |
5) Muscular force | c) Fruit falling from a tree |
Question 24.
Assertion (A): Magnetic force is a field force.
Reason (R) : A magnet can attract of repel another magnet with zero magnitude.
A) A and R are true
B) A and R are false
C) A is true, but R is false
D) A is false, but R is true
Answer:
C) A is true, but R is false
Question 25.
Take two balloons inflate them. Rub both with your hair. Bring them to closer to each other. Then they
A) Repels
B) Attracts
C) No change
D) We cannot say anything
Answer:
A) Repels
Question 26.
The net force in the diagram is
A) 8N
B) 16 N
C) 20 N
D) 4 N
Answer:
D) 4 N
Question 27.
Frictional force depends upon ____________
i) Normal force
ii) Gravitational force
iii) Area of contact
iv) Smoothness of surface
A) i, ii only
B) iii only,
C) i, ii and iv only
D) iv only
Answer:
C) i, ii and iv only
Question 28.
When two forces are acting in the same direction the resultant force is
A) sum of the forces
B) differences of forces
C) half of the fort es
D) zero
Answer:
A) sum of the forces
Question 29.
Effect of pressure depends upon _________
A) area of contact
B) force applied
C) frictional force
D) both A and B
Answer:
D) both A and B
Question 30.
Study the following table.
Case | i | ii | iii | iv |
Force (N) | 20 | 10 | 40 | 30 |
Area (m2) | 0.5 | 0.2 | 0.8 | 0.3 |
In which case the pressure is more ?
A) i
B) ii
C) iii
D) iv
Answer:
B) ii
Question 31
Choose correct matching option.
Group A | Group B |
A) Electrostatic force | i) Force |
B) Force per unit area | ii) Non contact force |
C) Muscular force | iii) Pressure |
D) Push or pull on object | iv) Contact force |
A) a – ii, b – iv, c – i, d – iii
B) a – iii, b – i, c – iv, d – ii
C) a – ii, b – iii, c – iv, d – i
D) a – iv, b – iii, c – i, d – ii
Answer:
C) a – ii, b – iii, c – iv, d – i
Group A | Group B |
A) Electrostatic force | ii) Non contact force |
B) Force per unit area | iii) Pressure |
C) Muscular force | iv) Contact force |
D) Push or pull on object | i) Force |
Question 32.
Which of the following statements is correct about a force ?
A) It can be seen but it can’t be felt
B) It is needed to start an object moving.
C) It can change the shape of an object.
D) It can make moving object stop
Answer:
A) It can be seen but it can’t be felt
Question 33.
Pressure can be increased by
A) Increasing both the area and the force.
B) Decreasing the area and increasing the force.
C) Increasing the area arid decreasing the force.
D) Decreasing both the area and the force.
Answer:
B) Decreasing the area and increasing the force
Question 34.
Pressure exerted by a sharp needle on a surface is
A) More than the pressure exerted by a blunt needle.
B) Less than the pressure exerted by a blunt needle.
C) Equal to the pressure exerted by a blunt needle.
D) None of these.
Answer:
A) More than the pressure exerted by a blunt needle.
Question 35.
In the given experiment which type of force is represented ?
A) Magnetic
B) Electrostatic
C) Gravitational
D) Tension
Answer:
A) Magnetic
Question 36.
From the given figure, the force which is pulling the cart is
A) contact force
B) force at a distance
C) muscular force
D) A and C
Answer:
D) A and C
Question 37.
From the above diagram
The force exerted by one rubber band is F. Then the net force acting on your finger when four rubber bands are used is
A) F
B) 2F
C) 3F
D) 4F
Answer:
D) 4F
Question 38.
Directions of normal forces labelled at
A) a, b
B) c, d
C) c
D) a, c
Answer:
A) a, b
Question 39.
X, Y are the objects having same size and made with same material. A nail of 1 kg on X and a screw of 1 kg on Y are placed. On which object the pressure is more ?
A) On X
B) On Y
C) equal pressure on X and Y
D) Data is insufficient
Answer:
A) On X
Question 40.
Suresh placed a book on the table.
Suresh asked his Mend Mahesh, Why is the book in rest even though two forces are acting on the book ?
Then Mahesh replied that
A) Normal force and gravitational forces are equal and acting in same directions.
B) Normal force and gravitational forces are unequal and acting in opposite directions.
C) Normal force and gravitational forces are unequal and acting in same directions.
D) Normal force and gravitational forces are equal and acting in opposite directions.
Answer:
D) Normal force and gravitational forces are equal and acting in opposite directions.
Question 41.
What do you generalise from above information ?
A) Limiting force depends on colour of the threads.
B) Different strings have different limiting forces.
C) Natural fibres are strong.
D) All type of strings have same limiting force.
Answer:
B) Different strings have different limiting forces.
Question 42.
Rajesh inflated a balloon and tied up the open end. Now cut a paper into small pieces and place them on the floor. Rub the balloon with a paper and bring the balloon near the pieces of a paper”. What would you conclude from this experiment?
i) No need of physical contact for contact forces
ii) Balloon acquires -an electrostatic charge on its surface
iii) In field force there is no physical contact
A) ii only correct
B) i and ii only correct
C) ii and iii only correct
D) i only correct
Answer:
C) ii and iii only correct
Question 43.
We use sharper side of a knife to cut vegetables than the blunt side because
A) Blunt side has a smaller contact area
B) Sharper side has a smaller contact area
C) Sharper side exerts less pressure
D) Blunt side exerts more pressure
Answer:
B) Sharper side has a smaller contact area
Question 44.
Study the figure given below. At which point, the pressure is greater?
A) I
B) II
C) III
D) IV
Answer:
C) III
Question 45.
Which of the following table do you choose to make data interpretation?
Answer:
A)
S. No. | Type of string | length of the string | Max limiting force |
Question 46.
A student did a set of experiments using a balloon and a glass rod. In which of the following experiments will the balloon be attracted to the glass rod ?
A) Experiment 1 : Negatively charged balloon brought near a negatively charged glass rod.
B) Experiment 3 : Positively charged balloon brought near a positively charged glass rod.
C) Experiment 2 : Negatively charged balloon brought near a positively charged glass rod.
D) Experiment 4 : Neutral balloon brought near a neutral glass rod.
Answer:
C) Experiment 2 : Negatively charged balloon brought near a positively charged glass rod.
Question 47.
In the picture below, glass P is filled with water and has a plastic sheet placed over it. Glass Q is identical to glass P and is filled with an equal amount of water. Glass Q has a plastic sheet below it.
Which of the following is true about the atmospheric pressure acting on the two plastic sheets ?
A) The atmospheric pressure is greater on the sheet in P.
B) The atmospheric pressure is greater on the sheet in Q.
C) The atmospheric pressure is equal in P and in Q.
D) Cannot say as water is touching the plastic sheet in Q, but not in P.
Answer:
C) The atmospheric pressure is equal in P and in Q.
Question 48.
Which of the following, when filled inside a closed container, can exert pressure on the inner walls of the container ?
P : Solids
Q : Liquids
R : Gases
A) Only P
B) Only Q
C) Only P and Q
D) All P, Q and R
Answer:
D) All P, Q and R
Question 49.
Three students in a Physics class were discussing the nature of forces. This is what they said :
Dinesh : a force may be a contact or a non-contact force.
Pradeep : a force can be measured as it has a magnitude.
Farhad : a force acts in a particular direction.
Who is correct ?
A) Only Dinesh
B) Only Dinesh and Pradeep
C) Only Dinesh and Farhad
D) All – Dinesh, Pradeep and Farhad
Answer:
D) All – Dinesh, Pradeep and Farhad
Fill in the blanks.
1. Force could be a ………………… .
Answer:
push or a pull
2. A ………………… arises due to the interaction between two objects.
Answer:
Force
3. Force has ………………… as well as ………………… .
Answer:
magnitude, direction
4. A change in the ………………… of an object or the ………………… of its motion or both implies a
change in its state of motion.
Answer:
Speed, direction
5. Force acting on an object may cause a change in its ………………… or a change in its ………………… .
Answer:
state of motion, shape
6. A ………………… can act on an object with or without being in contact with it.
Answer:
force
7. Force per unit area is called ………………… .
Answer:
pressure
8. ………………… and ………………… exert pressure on the walls of their containers.
Answer:
Liquids, gases
9. The pressure exerted by air around us is known as ………………… .
Answer:
atmospheric pressure
10. Force/ area = ………………… .
Answer:
pressure
11. Like pole of magnets ………………… each other.
Answer:
repels
12. ………………… causes to fall down the fruits from the trees.
Answer:
Gravity
13. If the area of contact increases pressure ………………… .
Answer:
decreases
14. Any moving object slows down due to ………………… force.
Answer:
frictional
15. Shape of an object can be changed by applying ………………… on it.
Answer:
force
16. Fill up the blanks with suitable words to complete the given statement. Air moves from ………………… pressure region to ………………… pressure region.
Answer:
high, low
17. The force acting on a body can change its ………………… .
Answer:
shape
18. The S.I. unit of pressure is ………………… .
Answer:
Pascal
III. Match the following.
Question 1.
Group – A | Group – B |
P) contact force | i) friction |
Q) non-contact force | ii) gravity |
iii) pressure |
Answer:
P – i, Q – ii
Group – A | Group – B |
P) contact force | i) friction |
Q) non-contact force | ii) gravity |
Question 2.
Group – A | Group – B |
P) contact force | i) reading a book by a boy |
Q) non-contact force | ii) pulling a nail by a magnet |
iii) pulling a cart by porter |
Answer:
P – iii, Q – ii
Group – A | Group – B |
P) contact force | iii) pulling a cart by porter |
Q) non-contact force | ii) pulling a nail by a magnet |
Question 3.
Group – A | Group – B |
P) pull | i) climbing a rope |
Q) push | ii) reading a book |
iii) bowling a ball |
Answer:
P – i, Q – iii
Group – A | Group – B |
P) pull | i) climbing a rope |
Q) push | iii) bowling a ball |
Question 4.
Group – A | Group – B |
P) preparing a paper boat | i) changing in motion |
Q) hitting a ball with a bat | ii) changing in direction |
iii) changing in shape |
Answer:
P – iii, Q – ii
Group – A | Group – B |
P) preparing a paper boat | iii) changing in shape |
Q) hitting a ball with a bat | ii) changing in direction |
Question 5.
Group – A | Group – B |
P) pulling a door | i) gravity |
Q) falling a leaf from a tree | ii) friction |
iii) muscular force |
Answer:
P – iii, Q – i
Group – A | Group – B |
P) pulling a door | iii) muscular force |
Q) falling a leaf from a tree | i) gravity |
Question 6.
Group – A | Group – B |
P) pull or push | i) pressure |
Q) force per unit area | ii) friction |
iii) force |
Answer:
P – iii, Q – i
Group – A | Group – B |
P) pull or push | iii) force |
Q) force per unit area | i) pressure |
Question 7.
Group – A | Group – B |
P) nail pointed edge | i) to increase pressure |
Q) porters wearing turban (talapaga) | ii) to reducing pressure |
iii) to reduce force |
Answer:
P – i, Q – ii
Group – A | Group – B |
P) nail pointed edge | i) to increase pressure |
Q) porters wearing turban (talapaga) | ii) to reducing pressure |