In physics, motion refers to the change in the state of something independent of the object’s position, direction and speed. This means that motion is independent of the observer. Motion is defined in terms of the object’s state and is measured using vectors. When we think of motion, we often think of things moving in a straight line. Whether it’s a car driving down the street, a rocket shooting across the sky or an aeroplane soaring in the sky, we often think of objects moving in a direction that can be described as a straight line. But how do we define a straight line and how do we measure it? It turns out that finding a single, universal definition of a straight line is surprisingly difficult.
Types of Motions in a Straight line:
Motion is the process through which objects move through space. In physics, motion is described by two main types: linear and nonlinear. Linear motion has a straight line path. In a straight line, an object moves at a constant speed and the direction in which the object moves is the direction in which the object is moving. This linear motion, also known as rectilinear motion, is subdivided into two types:
Uniform Linear Motion
Non-uniform Linear Motion
See AlsoStraight line graphs
Uniform Linear Motion:
The simplest type of motion is Uniform Linear Motion (ULM). In this type of motion, there is no change in the velocity and direction of the object at any point throughout the motion and hence, the acceleration is zero. The equation for ULM is given by the following: y = mx + v, where y is the displacement, m is the mass and v is the initial speed. This equation can be rearranged to be: y = mv + x, where v is the final speed.
Examples of Uniform Linear Motion:
Examples of Uniform Linear Motion are objects thrown in baseball and a rock thrown in a straight line at a constant speed and direction. In these two examples, the object is at rest and the only forces acting on it are those of gravity. Examples of ULM include a car moving at a steady speed, a rocket travelling at a constant speed and a train moving at a constant speed. In all of these examples, the object is moving in a constant direction and at a constant speed.
Non-uniform Linear Motion:
Non-uniform linear motion or NULM is a type of motion in which an object’s direction or speed does not remain constant. It occurs when objects move at different speeds and in different directions at the same time. The object changes direction or speed in a non-continuous manner, often requiring some amount of force to keep it moving. NULM can be used to describe a wide variety of motions, ranging from a car accelerating on a highway to a rocket moving through space. In many cases, NULM is used to describe a motion that is neither uniform nor linear.
Examples of Non-uniform Linear Motion:
NULM is important in many real-world situations, such as when a car moves through a city or a roller coaster that moves around a track. Examples of NULM also include the orbit of a planet, the path of a bullet fired from a gun and the flight of an aeroplane. In all of these cases, the object is moving in a straight line at some speed, but the direction of its movement is changing. The bullet is fired from a gun, but the direction of its movement is changing as it flies through the air.
First Law of Motion: Inertia
The inertia is the resistance that an object has to being moved. The first law of motion is the law of inertia, which describes the tendency of an object at rest to remain at rest and an object in motion to remain in motion. The first law of motion states that an object will remain in the state of motion and position it was in when it started unless an outside force is applied to it. This means that an aeroplane will continue to travel in the direction it is moving in unless a force is applied that causes it to change direction.
Equations of motion in a straight line:
When a moving object moves in a straight line, its trajectory is described by a set of simple mathematical equations. These equations can be used to predict the future position of an object, given its current position and speed. In other words, they describe the position of an object at a given time, when its current speed and direction are mentioned. Sometimes, the equations are simplified to just the two variables, speed and direction. These equations are:
v = u + at
s = ut + ½ at²
v²= u² + 2as
u = initial velocity,
v = final velocity,
a = acceleration,
s = displacement,
t = time taken to travel a distance s.
Conclusion:
Linear motion is motion in a straight line. It can be described as movement along a single axis. The two most common types of linear motion are Uniform Linear Motion and Non-uniform Linear Motion. Linear motions are easy to understand, because they move objects in direct proportion to the direction of the force that is acting on them. They are also relatively easy to describe in terms of other movements. Uniform Linear Motions have constant velocity and hence, zero acceleration whereas NULMs have variable velocity and hence, non-zero acceleration.
