Physics · Science General

Newtonian Mechanics and Forces

1,559 Questions

Newtonian mechanics studies the motion of objects and the physical laws governing them. This hub covers friction, gravitational force, inertia, and vector quantities. Mastering these fundamental physics concepts is essential for various government competitive exams.

Laws of motionFriction and inertiaVector and scalar quantitiesGravitational accelerationArchimedes principle

Newtonian Mechanics and Forces Questions

Multiple choice

Match the following:

 
a. Contact force 1. It is the force exerted by the muscles of the body.
b. Muscular force 2. It is the force, which can be exerted by an object on another object even from a distance, without touching each other.
c. Non-contact force 3. It is a force, which can be exerted by an object on another object only through physical touching.

  1. a - 3, b - 2, c - 1

  2. a - 3, b - 1, c - 2

  3. a - 1, b - 3, c - 2

  4. a - 1, b - 2, c - 3

  5. a - 2, b - 1, c - 3
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is the correct option. Contact force is a force, which can be exerted by an object on another object only through physical touching. Muscular force is the force exerted by the muscles of the body. Non-contact force is the force, which can be exerted by an object on another object even from a distance, without touching each other.

Multiple choice

Match the following:

 
a. Frictional force 1. It is a force exerted by a magnet.
b. Magnetic force 2. It is the force exerted by an electrically charged object.
c. Electrostatic force 3. It is a force, which always opposes the motion of one body over another body.

  1. a - 3, b - 2, c - 1

  2. a - 3, b - 1, c - 2

  3. a - 1, b - 3, c - 2

  4. a - 1, b - 2, c - 3

  5. a - 2, b - 1, c - 3
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is the correct option. Frictional force is a force, which always opposes the motion of one body over another body. Magnetic force is a force exerted by a magnet. Electrostatic force is the force exerted by an electrically charged object.

Multiple choice

Gravitation is the natural phenomenon responsible for objects with mass to

  1. repel each other

  2. attract each other

  3. explode

  4. fall on lighter objects
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Gravitation is a force of attraction between all objects with mass. Every object in the universe attracts every other object - that's why things fall toward Earth and planets orbit the Sun. The force increases with mass and decreases with distance.

Multiple choice

Which of the following is a force acting on an airplane in flight?

  1. Weight

  2. Lift

  3. Thrust

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Four fundamental forces act on an aircraft in steady flight: lift (opposes weight), weight (gravity pulling down), thrust (propels forward), and drag (opposes thrust). All of these forces are constantly acting on the airplane. The question's phrasing is slightly awkward since it asks 'which is a force' (singular) but the correct answer acknowledges that all listed forces act simultaneously.

Multiple choice

Which is not a vector quantity?

  1. Speed

  2. Acceleration

  3. Force

  4. Displacement
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Yes, it is correct as it has only magnitude. So it is a scalar quantity.

Multiple choice

As we move along a period

  1. the size of atom increases

  2. the size of atom decreases

  3. the size remains the same

  4. the size first increases then toward the end it decreases.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Yes, it is correct as no new shell is added and electrons are added in same shell which increases ionization energy . An increase in ionization energy means decrease in size.

Multiple choice

The principle involved in the working of the physical balance is

  1. Law of conservation of energy

  2. Law of conservation of linear momentum

  3. Law of conservation of angular momentum

  4. Principle of moments
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A physical balance works on the principle of moments (torque equilibrium). When the balance is level, the clockwise moment equals the anticlockwise moment. The product of mass and distance from the fulcrum must be equal on both sides for equilibrium to be achieved, which is the fundamental principle behind weighing scales.

Multiple choice

The force acting on a unit area is called

  1. surface tension

  2. buoyant force

  3. pressure

  4. thrust
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Pressure is defined as force per unit area (P = F/A). Surface tension is the force per unit length at a liquid's surface. Buoyant force is the upward force on a submerged object. Thrust is the total force acting perpendicular to a surface, not normalized by area.

Multiple choice

When milk is churned, the cream is separated due to

  1. gravitational force

  2. centrifugal force

  3. frictional force

  4. electro magnetic effect

  5. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When milk is churned, centrifugal force causes the denser components (including fat globules in cream) to separate based on density differences. Gravitational force acts uniformly and doesn't cause separation. Frictional force opposes motion, and electromagnetic effect is irrelevant to this mechanical separation process.

Multiple choice

The sensation of weightlessness in a spacecraft in an orbit is due to the _______.

  1. absence of gravity outside

  2. acceleration in the orbit which is equal to the acceleration due to gravity outside

  3. presence of gravity outside but not inside the spacecraft

  4. fact that spacecraft in the orbit has no energy
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The sensation of weightlessness occurs because the spacecraft and everything inside are in free fall - both are accelerating toward Earth at the same rate (equal to g). This creates a state of continuous free fall, where apparent weight becomes zero. There's still gravity in orbit; it's what keeps the spacecraft orbiting.

Multiple choice

Cream gets separated out of milk when it is churned. This is due to ______.

  1. gravitational force

  2. centripetal force

  3. centrifugal force

  4. frictional force
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Separating cream from milk through churning relies on centrifugal force, an apparent outward force experienced in a rotating reference frame. Denser components of milk move outward, while the less dense fat particles (cream) gather in the center.

Multiple choice

Newton 1st law of motion gives the concept of ______.

  1. energy

  2. work

  3. momentum

  4. inertia
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Newton's first law (law of inertia) states that an object at rest stays at rest and an object in motion stays in motion unless acted upon by an external force. This fundamental principle introduces the concept of inertia - an object's resistance to changes in its state of motion.

Multiple choice

With reference to a horizontal moving object on a floor, in which direction does the force of friction act?

  1. In a direction which is opposite to the direction of the moving object.

  2. In a direction, which is towards the direction of the moving object.

  3. In the downward direction.

  4. In the upward direction.

  5. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct option. The force of friction acts in a direction, which is opposite to the direction of the moving object.