A Detailed Guide To The Work, Kinetic Energy, And Conservation Of Energy

What is meant by work?

Work, in physics, can be defined as the displacement of an object in the direction in which force is exerted. The standard unit used to measure work is the joule (J), equivalent to a Newton-meter (N. m).

Here mentioned are some examples of the work: 

• Picking up an object against the earth’s gravitational force.
• Driving a car up to the mountain.
• Pulling down a helium balloon. 
• A mother is pushing a grocery cart in the shopping complex.

The mathematical formula to calculate work is:

W =Fd

Here, 

W = Work

F = Force

d = Distance of the object

What factors affect the work?

Here mentioned are the factors affecting the work:

• In physics, force is defined as the push or pull causing any object with a mass to change both its velocity and acceleration. Force is a vector quantity, and thus, it can be said that it has a magnitude and a direction.
• Displacement: Displacement, in physics, refers to a vector quantity giving the shortest distance between the object’s initial and final positions. In case the resulting displacement is in the same direction as the force because the force acting on the object is zero, then the network done by the force on the same object will be zero.

What is meant by kinetic energy?

Kinetic energy, in physics, can be defined as the energy an object has due to its motion. 

To accelerate the object, force must be applied. Apply the force requires one to do the work. Now that work is done, energy will be transferred to the object, and thus, the object will move at a new constant speed. It is the transferred energy that is called kinetic energy. The kinetic energy is dependent on the mass and speed achieved. 

The mathematical formula to calculate the kinetic energy is:

KE = 1/2 mv²

Here, 

KE = Kinetic Energy

m = mass of the body

v = velocity of the body

What does the principle of conservation of energy specify?

Conservation, in physics, refers to something that does not change. This implies that the variable in an equation representing the conserved quantity will be constant. It will have the same value before as well as after an event. 

The law of conservation of energy specifies that it is not possible to create or destroy energy, but it can only be converted from one form to the other form. When taking all forms of energy into account, an individual will find that the total energy of an isolated system always remains constant. All forms of energy that have been discovered follow the law of conservation of energy. 

So, it can be said that in an isolated system like the universe, if there is a loss of energy in some part of it, there essentially must be an equal amount of energy in some other part of the universe again. 

Following mentioned is the equation determining the amount of energy in any system:

Ut = Ui + W + Q

Here,

Ut = Total energy of the system

Ui = Initial energy of the system

W = Work done on the system or by the system

Q = Heat added or removed from the system 

Following is the equation that determines the change in the internal energy of the system:

ΔU = W + Q

Mentioning the examples of the Law of Conservation of Energy:

In physics, almost every invention depends on the fact that energy is conserved when transferred from one form to another. Here mentioned are some examples of the law of conservation of energy:

• In the torch, the chemical energy present in the batteries is converted into electrical energy, which is further converted into light and heat energy.
• The waterfalls on the turbines from the height in the hydroelectric power plants cause the turbines to rotate and generate electricity. Hence, the water’s potential energy is converted into kinetic energy of the turbine, which is converted into electrical energy.
• When food is broken down in the body, the chemical energy from food is transformed into thermal energy keeping the body warm.

Conclusion

Whenever a force is exerted on an object causing it to displace, the work is said to have been done upon the same object by that certain force. Kinetic energy is the energy an object has because of its motion. The law of energy conservation states that energy can’t be created or destroyed but can only be transferred from one form to the other. To know more about work, kinetic energy, and the law of energy conservation, it is suggested to go through the article mentioned above.