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 physics along with motion what forces can do? force and it's unit force and its effects

An object is subjected to a non-zero net force, $F$. Which of the following statements about its motion could not be true?

  1. The object will remain at rest

  2. The object has a constant velocity

  3. The object is travelling in a straight-line path with a constant speed

  4. The object is travelling in a circular path with a constant speed

  5. The acceleration of the object is perpendicular to the net force
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Net force on an object is directly proportional to the acceleration of the particle which is the rate of change of velocity.

When a body moves in a uniform circular motion, its velocity keep on changing though its speed is constant.

Multiple choice physics along with motion what forces can do? force and it's unit force and its effects

Which of the statements about force are true?

  1. It can be seen

  2. It causes an object to move

  3. It is pull or a push

  4. It can change the motion of an object
Reveal answer Fill a bubble to check yourself
B,C,D Correct answer
Explanation

The force can net be seen but we can see the effects of the force. The force is a pull or a push. The effect of forces are like as it causes an object to move, it can change the motion of the body, it can change shape or volume of the body. 

Multiple choice physics along with motion what forces can do? force and it's unit force and its effects

Force is an external effect in the form of a push or pull, which ..................

  1. Produces or tries to produce motion in a body at rest

  2. Stops or tries to stop a moving body

  3. Changes or tries to change the direction of motion of the body

  4. None of these
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

When force is applied in the direction of motion it increases velocity,

when applied opposite to the direction of motion it will try to reduce the velocity.
when force is applied at any angle with velocity of object, it will try to give a component in that direction where force is applied hence direction or magnitude of net velocity is changed.
When force is applied to any body, an acceleration is generated in that direction where force is applied.

Multiple choice physics along with motion what forces can do? force and it's unit force and its effects

You are on a frictionless horizontal plane. How can you get off if no horizontal force is exerted by pushing against the surface?

  1. By jumping

  2. By splitting or sneezing

  3. By rolling your body on the surface

  4. By running on the plane
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

While splitting or sneezing you will exhale things out with some momentum by applying force on it and in return you will experience a force in the opposite direction according to the $Newton's\quad Third\quad Law\quad of\quad Motion$.So, in this way you will aquire a velocity on a frictionless surface and you will be able to get off it.

Multiple choice physics along with motion what forces can do? force and it's unit force and its effects

A rider on horse falls back when horse starts running all of a sudden because

  1. Rider is taken back

  2. Rider is suddenly afraid of falling

  3. Inertia of rest keeps the upper part of body at rest while lower part of the body moves forward with the horse.

  4. Inertia of motion keeps the upper part of body at rest while lower part of the body moves forward with the horse.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A rider on horse falls back when horse starts running, all of a sudden because the rider is in state of rest initially and later inertia of rest keeps the upper part of body at rest while lower part of the body moves forward with horse.

Multiple choice physics along with motion what forces can do? force and it's unit force and its effects

If a body is moving with a constant speed along a straight line; then in order to change its direction of motion, an external force has to be applied in a direction normal to the direction of motion.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Newton's First law of motion - "Every body continues to be in its state of rest or of uniform motion in a straight line unless compelled by some external force to act otherwise". 

According to Newton's First law of motion, statement is true, an external force has to be applied in a direction normal to the direction of motion to change its direction of motion

Multiple choice physics along with motion what forces can do? force and it's unit force and its effects

Three forces are acting on a body in which of following option (s) can the body be in equilibrium?

  1. $2N, 4N, 5N$
  2. $1N, 2N, 4N$
  3. $3N, 3N, 7N$
  4. $5N, 2N, 1N$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Three force are in equilibrium if 

1) All forces are in a plane 
2) Sum of two small forces is less than bigger force.
This condition is satisfy by option A
Answerer A

Multiple choice physics along with motion what forces can do? force and it's unit force and its effects

A force produces transnational motion:

  1. when the body is free to move

  2. when the body is hindered to move

  3. when the body is rigidly fixed

  4. when none of the above are true
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For the application of translational motion the body must be free to move and after applying force, all the particles in that body move with same velocity.