Concept of Energy

 

Anything that has the ability to do work possesses some form of energy. A boy running along a race track possesses the energy to do so. A man pushing a car over a certain distance also possesses energy to move the car. Even a mango fruit which drops from the tree under gravity also possesses the energy to do so. These therefore implies that for a body to do work, it must have the energy to perform the designated task.

Concept of Work

The term 'work' is used in everyday life for different purposes. Mostly, it is used when there is a physical activity that requires much effort.

However, in physics the term work is used in a very specified manner most especially in mechanics. Hence we will be defining and explaining the concept of work in its real physical sense.

Definition of Work

Work is said to be done when the application of force causes

Advantages and Disadvantages of Friction

Previously, we learnt that friction is simply a force that tends to oppose the motion of a surface over another. These opposition can be used to an advantage or even become a disadvantage to the two surfaces in contact. Let's consider some examples of the advantages and disadvantages of friction;

Friction

 

When you rub two solids together usually with rough surfaces, you will observe that they will not slide freely over each other. This is as a result of the roughness of their surfaces which tends to oppose the motion of one surface over the other. This is as a result of the effect of friction.

Friction can be defined as a force which acts between the surface of two solids in contact. It tends to hinder the movement of one of the solids over the other.

Friction can also be said to be a force of opposition which acts

What causes motion?

In my previous posts, we have discussed motion, the different types of motion and some physical quantities associated with the motion of a body. All these have been discussed without regard for the actual cause of motion. Have you ever wondered why a body at rest would move, a moving body continues in uniform motion or why a body at rest remains at rest?

Speed, Velocity and Acceleration

In motion, it is important to understand some quantities involved with the movement of a body in a straight line. The essential quantities are distance, displacement, speed, velocity and acceleration.

 Speed

The speed of a body in motion is the rate at

Position, Distance and Displacement

 

Position

The position of a point is its location in space from a reference point (called origin) usually on a cartesian plane. It is determined by its distance and direction from