The following 20 Multiple Choice Questions (MCQ) are based on
Chapter 5: Exploring Forces from the NCERT Class 8
Science textbook Curiosity. Each question has four options - select the
best answer and click to check.
Instructions: Read each question carefully. Choose the most
appropriate option from (a), (b), (c), or (d). Click
Show Answer to reveal the correct answer with explanation.
Multiple Choice Questions
1A force is scientifically described as a:
(a) Push or pull
(b) Form of temperature
(c) Type of material
(d) Unit of mass
(a) is correct
Forces arise through interactions and can be experienced as pushes or pulls.
2Which change can a force produce?
(a) Change time
(b) Remove all mass
(c) Create matter from nothing
(d) Change speed, direction or shape
(d) is correct
A force can alter motion or deform an object.
3A force always involves:
(a) A change in colour
(b) An electric circuit
(c) An interaction between objects
(d) Only one object with no surroundings
(c) is correct
One object exerts a force on another through contact or at a distance.
4Which is a contact force?
(a) Magnetic force across a gap
(b) Friction
(c) Gravity
(d) Electrostatic force
(b) is correct
Friction acts where two surfaces touch.
5Which is a non-contact force?
(a) Muscular force while lifting
(b) Friction
(c) Gravitational force
(d) Normal force from a table
(c) is correct
Gravity acts between masses without physical contact.
6Friction acts mainly to:
(a) Increase motion in every case
(b) Remove gravity
(c) Change mass
(d) Oppose relative motion between surfaces
(d) is correct
It resists slipping or the tendency to slip.
7Why is it easier to slip on a wet polished floor?
(a) Mass becomes zero
(b) The floor exerts no force
(c) Water reduces friction between surfaces
(d) Gravity disappears
(c) is correct
The water layer lowers grip between footwear and floor.
8Which action uses friction beneficially?
(a) Reducing tyre grip
(b) Walking without slipping
(c) Wearing out machine parts
(d) Heating unwanted surfaces
(b) is correct
Static friction between foot and ground lets us push backward and move forward.
9A ball rolling on level ground eventually stops mainly because of:
(a) Friction and air resistance
(b) Increasing gravity
(c) Electrostatic attraction only
(d) Loss of mass
(a) is correct
Resistive forces act opposite its motion and reduce its speed.
10Two similarly charged balloons brought close together will:
(a) Attract
(b) Lose all mass
(c) Show no electrostatic interaction
(d) Repel
(d) is correct
Like electric charges repel each other.
11A magnet attracting an iron nail demonstrates:
(a) Buoyant force
(b) Muscular force
(c) A non-contact magnetic force
(d) Only friction
(c) is correct
The magnetic interaction can act across a small gap.
12Weight is the force exerted on an object by:
(a) Buoyancy only
(b) Gravity
(c) Friction only
(d) Electric current
(b) is correct
Weight measures the gravitational pull on an object's mass.
13Which instrument measures weight or force?
(a) Spring balance
(b) Beam balance only
(c) Thermometer
(d) Stopwatch
(a) is correct
A calibrated spring balance measures force in newtons.
14The SI unit of weight is:
(a) Newton
(b) Litre
(c) Second
(d) Kilogram
(a) is correct
Weight is a force, so its SI unit is the newton.
15An object's mass on the Moon compared with Earth is:
(a) Six times
(b) Zero
(c) The same
(d) One-sixth
(c) is correct
Mass is the amount of matter and does not depend on local gravity.
16An object's weight on the Moon is about:
(a) Zero in every place
(b) The same as on Earth
(c) One-sixth of its Earth weight
(d) Six times its Earth weight
(c) is correct
The Moon's gravitational field is about one-sixth as strong as Earth's at the surface.
17The upward force exerted by a fluid on an immersed object is:
(a) Buoyant force or upthrust
(b) Friction only
(c) Weight
(d) Electrostatic force
(a) is correct
Fluids exert an upward resultant force on immersed objects.
18An object floats at rest when its weight is:
(a) Greater than every upward force
(b) Zero
(c) Converted into mass
(d) Balanced by buoyant force
(d) is correct
The downward gravitational force and upward buoyant force balance.
19A coin sinks while a larger wooden block may float because floating depends mainly on:
(a) Colour
(b) Whether the object is shiny
(c) Average density and buoyant force, not size alone
(d) Size alone
(c) is correct
A sufficiently low average density lets an object displace enough water for upthrust to balance weight.
20At the topmost point of a ball thrown upward, which force still acts on it if air resistance is ignored?
(a) Buoyancy upward only
(b) Gravity downward
(c) An upward throwing force
(d) No force
(b) is correct
Its velocity is momentarily zero, but Earth's gravitational pull continues downward.
