Newton's Third Law of Motion

The string between blocks of mass $m$ and $2m$ is massless and inextensible. The system is suspended by a massless spring as shown. If the string is cut find the magnitudes of accelerations of mass $2m$ and $m$ (immediately after cutting)

Magnetic force is example of _____ force.

Which one of given force is not example of internal force?

Which of the given force is not external force?

Can a single isolated force exist in nature? Explain your answer.

Why is it not possible to push a car from inside?

Two bodies A and B of masses $5 \mathrm{kg}$ and $10 \mathrm{kg}$ in contact with each other rest on a table against a rigid wall as shown in the figure. The coefficient of friction between the bodies and the table is $0.15$. A force of $200 \mathrm{N}$ is applied horizontally to A. What are:

(a) the reaction of the partition?
(b) the action-reaction forces between A and B?

What happens when the wall is removed? Does the answer to (b) change, when the bodies are in motion? Ignore the difference between ${\mu }_s$ and ${\mu }_k$.

Among the following statements, the one that is not true regarding the Newton’s third law of motion is,

Action and reaction _____ act on the same body.

(Choose from: can/cannot)

Newton’s third law of motion can be derived as a second special case of Newton’s _____ law of motion.

A body of mass 2 kg moving on a horizontal surface with an initial velocity of 4 m/s comes to rest after 2 sec. If one wants to keep this body moving on the same surface with a velocity of 4 m/s, the force required is

Assertion: Newton's third law of motion is applicable only when bodies are in motion.

Reason: Newton's third law applies to only forces, e.g. gravitational, electricstatic forces etc.

Assertion: Nuclear force doesn't obey Newton's third law.

Reason: Nuclear force is not a central force.

Assertion: The third law of motion concludes that the forces occur in pairs of action and reaction.

Reason: The action force is more than the reaction force.

Assertion: Newton's third law is not applicable for nuclear forces.

Reason: Nuclear forces are short-ranged.

The force exerted by the ideal string on the ideal pulley $P$ shown in the figure is___

A bird is sitting in a large closed cage which is placed on a spring balance. It records a weight of $25 \mathrm{N}$. The bird $(mass\mathrm{ }m = 0.5 \mathrm{kg})$ flies upward in the cage with an acceleration of $2\mathrm{ }\mathrm{m} {\mathrm{s}}^{-2}$. The spring balance will now record a weight of

A parrot sitting on the floor of a wire cage which is being carried by a boy, starts flying. The boy will feel that the cage is now

Consider a horse pulling a wagon. Which of the statements below is the correct one ?