Equilibrium of Bodies

Question 1: Represent stable equilibrium pictorially.

Answer: 

Considering a cone of radius and height ‘H’, now place the cone on a smooth horizontal surface with its base touching the horizontal surface and then tilt it. It can be observed that the cone will retain its original position. This is a standard example of stable equilibrium.

Stable Equilibrium

Question 2: Represent Unstable equilibrium pictorially.

Answer: 

Considering a cone of radius and height ‘H’, now invert the cone and place it on a smooth horizontal surface and tilt it. It can be observed that the cone will not retain its original position. This is a standard example of unstable equilibrium.

Unstable Equilibrium

Question 3: Represent Neutral equilibrium pictorially.

Answer: 

Considering a cone of radius and height ‘H’, now place the cone with its slant face along the horizontal surface and then disturb it. It can be observed that the cone comes to rest after a certain time but it can’t attain its original position. This is a standard example of neutral equilibrium.

Neutral Equilibrium

Question 4: What is the connection between potential energy and conditions of equilibrium?

Answer:

For stable equilibrium d²U/dx² > 0, for unsteady equilibrium d²U/dx² < 0, and for normal equilibrium d²U/dx² = 0.

U is the potential energy of the object.

The laws of motion, which are the foundation of old-style mechanics, are three explanations that portray the connections between the forces following up on a body and its movement. They were first expressed by English physicist and mathematician Isaac Newton. The motion of an item is related to the forces operating on it by Newton’s equations of motion. According to the first law, until a force acts on an item, it will not alter its motion. According to the second law, an object’s force equals its mass times its acceleration.

First Law Of Motion

According to Newton’s first law, Everybody continues to be in its state of rest or uniform motion until and unless an external force acts on the body. This law is also called as Law of Inertia. This is the most practical law which we can experience daily while driving a bike or travelling on a bus.

Second Law Of Motion

According to Newton’s second law, For an object of constant mass, the rate of change of momentum is the force acting on the body. Thus the product of mass and acceleration gives the magnitude of the force acting on the body.

F = d/dt(mv)

= m.(dV/dt)

= m.a

Hence, F = m.a m/s²

Third Law Of Motion

According to Newton’s third law, Every action on a body has an equal and opposite reaction. Example: Shooting using a rifle, Frictional force acting on the shoe while we walk.