CBSE Class 8 Science Force and Pressure Worksheet Set A

 

            

 

Questions

              Very Short Answer

Q1)       Define force?

Q2)       How the force of friction arises?

Q3)       How the strength of force is expressed?

Q4)       Define muscular force?

Q5)       How force arises?

            Short Answer

Q6)       How the forces applied on an object?

Q7)       How forces are due to an interaction?

Q8)       What do you mean by state of motion?

Q9)       What happens when two forces acting on the opposite directions are equal?

Q10)     When does the force come into play?

             Long Answer

 Q11)     Distinguish between contact forces and non-contact forces?

Q12)     What are the characteristics of the force?

Q13)     Write short note on friction?

Q14)     State the difference between balanced forces and unbalanced forces?

Q15)     Write short note on muscular force?

 

Question. 1. Which of the following action describes pushing by a body?
(a) kicking
(b) lifting
(c) picking
(d) opening
Answer: A

Question. 2. Which of the following is not a type of force?
(a) muscular
(b) magnetic
(c) chemical
(d) pulling a bucket of water from a well
Answer: C

Question. 3. A force is applied to an object in the direction of its motion. The speed of object will
(a) increase
(b) decrease
(c) can't say
(d) remain unchanged
Answer: A

Question. 4. If no force acts on a body it will .....................
(a) change shape
(b) move with increased speed
(c) either remain in rest or move in a straight line
(d) break up
Answer: C

Question. 5. In football, a goal keeper stops a ball. This is due to:
(a) friction between the ball and hand of goal keeper
(b) decrease in speed of ball due to air resistance
(c) application of force by goal keeper
(d) all of the above
Answer: C

Question. 6. Which of the following example describes change of shape by applying force?
(a) kicking a ball to move faster
(b) switching on a fan to rotate
(c) jumping from a height
(d) tearing a paper into two pieces
Answer: D

Question. 7. Friction force is responsible changing:
(a) shape of an object
(b) direction of an object
(c) speed of an object
(d) all of the above
Answer: C

Question. 8. The force of friction between two bodies is:
(a) parallel to contact surface
(b) perpendicular to contact surface
(c) inclined to contact surface
(d) a non contact force
Answer: A

Question. 9. Which of the following is a non contact force?
(a) muscular
(b) electrostatic attraction
(c) elastic spring force
(d) friction force
Answer: B

Question. 10. A force of \( 16 \, \text{N} \) is distributed uniformly on one surface of a cube of edge '8' cm. The pressure on this surface is:
(a) 3500pa
(b) 2500 pa
(c) 4500 pa
(d) 2000 pa
Answer: B

Question. 11. The atmospheric pressure is due to the:
(a) sky above our head
(b) air mass surrounding earth
(c) gravitational force of sun and other planets
(d) mass of the earth
Answer: B

Question. 12. The pressure exerted by a liquid:
(a) increases with depth
(b) decreases with depth
(c) is constant
(d) first increases then decreases
Answer: A

Question. 13. Which of the following statement is not true.
(a) A freely falling body is acted upon by gravitational force
(b) Pressure on top of mount everest is much more than 1 atm
(c) S.I. unit of pressure is pascal
(d) The blood vessels in our body maintains the internal pressure equal to the atmospheric pressure
Answer: B

Question. 14. Thrust is:
(a) Force X area
(b) Force / Area
(c) Pressure
(d) Pressure X Area
Answer: D

Question. 15. A body floats in water because:
(a) no force is acting on it
(b) the net force acting on this body is zero
(c) of gravitational pull
(d) friction between body and the water
Answer: B

Question. 16. In which of the following cases the net force is not equal to zero?
(a) A kite skillfully held stationary in the sky
(b) A ball falling feeely from a height
(c) A helicopter hovering above the ground
(d) A cork floating on the surface of water
Answer: B

Question. 17. A car accelerates on a horizontal road due to the force exerted by:
(a) the engine of the ear
(b) the driver of the car
(c) the earth
(d) the road
Answer: D

Question. 18. While walking on ice, one should take small steps to avoid slipping. This is because smaller steps ensure:
(a) larger friction
(b) smaller friction
(c) larger normal force
(d) smaller normal force
Answer: D

Question. 19. In which of the following activity, friction is useful?
(a) driving a car
(b) hitting a ball with bat
(c) rowing a boat
(d) sitting on a chair
Answer: D

Question. 20. Friction can be increased by:
(a) making the surfaces rough
(b) using dry surfaces
(c) increasing the weight
(d) all of the above
Answer: D