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# Examples of Uniform Linear Motion

We will first describe the definition of motion before moving on to the examples of uniform linear motion and its definition.

Motion is when an object or body moves with respect to a particular point that we call as a reference point. Linear motion is when an object moves in a straight line. The path in which an object or a body is moving should be straight.  Now this linear motion or the motion along the straight line can be in two ways – it can be uniform or it can be non-uniform. If it is uniform linear motion then the object or the body will be moving in a straight line and covering equal distances in equal intervals of time. This means that the speed of the body will be a constant. Now as the speed is constant it further implies that the body will not be experiencing any kind of acceleration. However the case of non-uniform linear motion is different. In this kind of motion the body will be moving in a straight path or line but will experience acceleration. This means that it will move with different speed during intervals of time or it will be covering more or less distance in subsequent equal intervals of time.

Let us now take a few examples of uniform linear motion. Consider a car moving on a straight road. Consider that the car covers 40 kms in first 1 hour, 40 kms in the next one hour and 40 kms in the upcoming one hour. This will be an example of uniform linear motion as the speed is constant and hence there is no acceleration. This is because the car covers equal distances in equal intervals of time.

Consider a person walking on a straight footpath. The person covers 1 kilometer in half an hour and 2 kilometers in the next half hour. Now this will not be uniform linear motion. This will be non-uniform linear motion because although the person is moving in a straight line however his speed is not constant. So if there is no external agent which influences the speed of a moving body the body will hence continue to be in the state of motion with the constant speed. However this does not happen because we have free agents like force of friction which come in to play during such phenomena.

Consider a boy running a race of 800 meters. This boy completes the first lap of this race in three minutes. Now the path is straight and after every 400 meter the person hands over the baton to another person. So let us assume that in the 800 meters race the race is completed in 6 minutes. So this is an example of uniform linear motion as the time taken to complete both the 400 meter distances is constant and hence the speed can be considered constant. As the speed is constant we do not have any acceleration and so this is uniform linear motion.

From Wikipedia

Linear motion

Linear motion is motion along a straight line, and can therefore be described mathematically using only one spatial dimension. It can be uniform, that is, with constant velocity (zero acceleration), or non-uniform, that is, with a variable velocity (non-zero acceleration). The motion of a particle (a point-like object) along the line can be described by its position x, which varies with t (time). Linear motion is sometimes called rectilinear motion.

An example of linear motion is that of a ball thrown straight up and falling back straight down.

The average velocity v during a finite time span of a particle undergoing linear motion is equal to

v = \frac {\Delta d}{\Delta t}.

The instantaneous velocity of a particle in linear motion may be found by differentiating the position x with respect to the time variable t. The acceleration may be found by differentiating the velocity. By the fundamental theorem of calculus the converse is also true: to find the velocity when given the acceleration, simply integrate the acceleration with respect to time; to find displacement, simply integrate the velocity with respect to time.

This can be demonstrated graphically. The gradient of a line on the displacement time graph represents the velocity. The gradient of the velocity time graph gives the acceleration while the area under the velocity time graph gives the displacement. The area under an acceleration time graph gives the velocity.

Linear motion is the most basic of all motions. According to Newton's first law of motion, objects not subjected to forces will continue to move uniformly in a straight line indefinitely. Under every-day circumstances, external forces such as gravity and friction will cause objects to deviate from linear motion and can cause them to come to a rest.

For linear motion embedded in a higher-dimensional space, the velocity and acceleration should be described as vectors, made up of two parts: magnitude and direction. The direction part of these vectors is the same and is constant for linear motion, and only for linear motion

Question:the concept is from physics, reveal the truth and misconception related to it

Answers:The movement may be sustaining a constant speed, but the body receives a constant acceleration: the centripetal force. If this force is of constant amplitude, it however changes constantly in direction!

Question:Please give me the definition of the uniformly accelerated linear motion. Thanks.

Answers:Motion implies momentum, which implies velocity. Linear implies a straight line. Accelerating implies changing velocity. And uniform implies constancy. So, when a body moves in a straight line and accelerates at a constant rate, the body is said to have an uniformly accelerated linear motion.

Question:Related to ATWOOD MACHINE

Answers:Uniform linear motion is motion in which the velocity is unchanged in magnitude and direction. In other words, its acceleration is 0. The equations of that motion are: a = 0 v = constant x = vt + x0 (x zero is the initial coordinate) Uniformly accelerated/decelerated motion is motion in which the magnitude of the velocity increases/decreases uniformly over time, that is it changes the same amount in 1 unit of time at every moment. This motion has a constant acceleration a. The motion is uniformly accelerated or uniformly decelerated depending on whether a > 0 or a < 0. The equations of that motion are: a = constant, positive or negative, but different from 0. v = at + v0 (v zero is the initial velocity) . . . . . . . . (v - v0) / t is the same at all time t x = at + v0t + x0

Question:A train slows down as it rounds a sharp horizontal turn slowing from 90.0 km/h to 50.0 km/h in the 15.0 s that it takes to round the bend. The radius of the curve is 150 m. Compute the acceleration at the moment the train speed reaches 50.0 km/h. Assume that it continues to slow down at this time at the same rate. Need help...I've been working on this problem for about an hour!

Answers:First of all this is not a uniform circular motion problem. The train is slowing down. You are asked the to find the acceleration at a particular instant. Acceleration is a vector, meaning that it has magnitude and direction. The linear acceleration is just v(final) - v(initial) divided by the time. You have that information (although you need to get the units right). The centripetal acceleration is v(squared) divided by r. You also have that information. Because these two accelerations are perpendicular to each other, the magnitude of the overall acceleration is the square root of the the sum of the squares of each acceleration. (Sorry about not having mathematical symbols available here). To get the direction of the acceleration, use trigonometry of the right triangle