Why Newton’s second law is the real law of motion

In my one of earlier articles on Newton’s law, I have discussed about the Newton’s second law. We all are also aware about the Newton’s first law which mainly states that if an object is at rest will remain at rest and if it is in uniform motion will remain in uniform motion until and unless some external force is applied on it. Continue reading “Why Newton’s second law is the real law of motion”

Difference between force and torque

Students often asked me what is the difference between force and torque? We might be aware about these terms that is force and torque. Let us understand the concept of force. Force according to a layman is an effort to change the state of a body from rest to motion or from motion to rest and it may also defined as an effort which tries to change the state but it may not change the state. For example, there may be heavy stone and we can try to change its state of rest but we may not be possible to do the same. Continue reading “Difference between force and torque”

Difference between conservative and non conservative forces

We all are aware about the concept of force, if not then force may be defined as any push or pull that can change the state of rest of an object or can change the velocity of the moving object or can change the direction of the object. Forces can be classified into two types: conservative and non conservative forces. To understand the concept of these two, we also must be aware about the concept of work. The work is said to be done when a body actually moves a distance along the direction of the force. Now let us discuss the difference between the conservative and non conservative force: Continue reading “Difference between conservative and non conservative forces”

3 examples of Inertia of direction

As we have already discussed that the inertia of direction is defined as the inability of a body or object to change its direction of motion by itself. That is external force is required to change its direction of motion. Let us discuss the 3 examples of inertia of direction:

  1. Mud through rotating wheels: we have seen that the rotating wheels of a vehicle throughout mud in a tangential direction. This is due to inertia of direction. This is the reason that the mud guards are provided in vehicles over the wheels to stop this mud so that to protect the clothes. Continue reading “3 examples of Inertia of direction”

impulse force and its applications

Impulsive Forces: The force which act on a body for a short time are known as Impulsive forces.

For eg. Hitting a ball with bat fining a gun etc.

An Impulsive force doe snot remain constant but changes, firstly from zero to max and then from max. to zero.

So it is not possible to measure the exact value of force. Hence in such cases, we measure the total effect of force known as Impulse. Continue reading “impulse force and its applications”

Derive relation F = ma from Newton 2nd Law of Motion

Let us derive the relation of force F = ma from Newton’s second law:

According to the Newton’s 2nd Law of motion, the rate of change of linear momentum of a body is directly proportional to the applied external force and in the direction of force.

It means that the linear momentum will change faster when a bigger force is applied.

Consider a body of mass ‘m’ moving with velocity v.

The linear momentum of a body is given by: Continue reading “Derive relation F = ma from Newton 2nd Law of Motion”

Types of Inertia

There are basically three types of Inertia-:

(a) Inertia of Rest: The inability of a body to change by itself its state of rest is known as Inertia of Rest.

Examples:

(i) Person sitting in a car falls backwards, when the car suddenly starts. It is because the lower portion in contact with the car comes in motion where as the upper part tries to remain at rest due to inertia of rest.

(ii) When we shake the branch of a tree, the leave or the fruits falls down because the branches comes in motion  where as the leaves or the fruit tends to remain at rest and hence gets detached. Continue reading “Types of Inertia”

What are Newton’s Laws of motion

The following are the Newton’s laws of motion :

Newton’s I Law: A body continues to in its state of rest or of uniform motion along a straight line unless an external force is applied on it.

Show that Newton’s 1st Law of Motion defines force?

According to the law of motion, a body continues to be in its state of rest or of uniform along a straight line unless it is acted upon by an external force.

So, we define force in the form of a push or pull which may change or tends to change the state of rest or of uniform motion of a body.

Newton’s II Law: The rate of change of linear momentum of the body is directly proportional to the external force applied on the body and this change takes place in the direction of the applied force.

Discuss the consequences of Newton’s 2nd Law of Motion. Continue reading “What are Newton’s Laws of motion”

Force, inertia and linear momentum

Force: The pull or push which change or tends to change the state of rest or of uniform motion or direction of motion of an object is called Force.

The units and dimension of force:

 

We know that                                  F = ma

There are two types of units of force

(i) Absolute Units:

(a) In M.K.S or S.I unit, the absolute unit of force is Newton (N)

Where                                                    1N = 1kg ´ 1m/s2

So 1N is the force which produces an acceleration of 1m/s2 in a body of mass 1 kg. Continue reading “Force, inertia and linear momentum”