Question

newtons 3 laws of motion are

Answer 1

Answer:

Explanation: First law: In an inertial frame of reference, an object either remains at rest or continues to move at a constant velocity, unless acted upon by a force.[2][3]

Second law: In an inertial frame of reference, the vector sum of the forces F on an object is equal to the mass m of that object multiplied by the acceleration a of the object: F = ma. (It is assumed here that the mass m is constant – see below.)

Third law: When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.

Answer 2

Newton's Three Laws of Motion

1.An object tends to remain in its state of rest or uniform motion in a straight line unless compelled to change its state by an external force.

To understand this concept we must understand what is inertia. Inertia is the inability of a body to change its state of rest, uniform motion along a straight line or direction on its own. The first law of motion is also called the law of Inertia.

• Consider a situation in which you are currently in a bus, which is at rest. The bus suddenly starts from rest, and when it does so, you move backwards. This is because the lower part of our body tends to maintain its state of rest, even when the bus starts from rest. This is termed as inertia of rest.
• Imagine that the bus you're travelling in is still in motion, and suddenly, it stops, and you move forward.This is because the lower part of our body tends to maintain its state of motion, even when the bus stops from motion. This is termed as inertia of motion.
• Consider that the bus you are travelling in is still in motion, and it makes a turn. Simultaneously, you move to the opposite side. This is because the body is unable to change its direction suddenly with respect to the change of direction of the bus. This is termed as inertia of direction.

2. The rate of change of momentum of an object is directly proportional to the applied unbalanced force in the given direction of force.

To understand the second law of motion we must first understand the concept of momentum. Momentum(P) is defined as the product of the mass(m) and velocity(v) of a given object. I.e.,

P=mv

The SI unit of momentum is kgm/s.

Momentum is of two types-

• Initial Momentum(mu)
• Final Momentum(mv)

From this we can derive the following formula:

F=ma

Some real-life applications of second law of motion are as follows:

• A fielder lowers his hands while taking a catch as to lower the momentum and to prevent his palms from getting hurt.
• A karate player is able to break a slab of ice with a single blow. This is because the acceleration of his arm increases tremendously. As the acceleration increases, force also increases. So the applied force is enough to break the slab of ice.

3.For every action there is an equal and opposite reaction.

The third law of motion states that when one object exerts a force on another object, the second object instantaneously exerts a force back on the first. The two forces are equal in magnitude but opposite in direction.Tjese forces act on different objects and never on the same object.

Some real-life applications of the third law of motion are as follows:

• When a gun is fired, it exerts a forward force on the bullet.The bullet exerts an equal and opposite reaction force on the gun. Since the gun has a greater mass than the bullet, the acceleration of the gun is much less than the acceleration of the bullet. So, the bullet moves a great distance forward, whole the gun just moves backwards.
• Consider a sailor jumping out of a rowing boat. The sailor would move forward, the force he exerts on the boat makes it move backwards.