Position Formulas - Change in Position Formula and Examples
Physics is one of the most fundamental scientific disciplines. It aims to study that portion of natural science which deals with motion, behavior, energy, and force, through space and time.
In this particular article, we will discuss one such important topic of Physics, related to Position. The team of experts has explained the concepts in the simplest language for the students to grasp them without much difficulty.
In this article, students will be able to learn the following concepts:
Position Formulas - Introduction
In order to know the motion of an object, it is important to understand its position. To describe the position, we need to take a point of reference. Often, we make use of the Earth as a point of reference to identify the position of an object. The point to note here is that we should take the reference which is generally not in a stationary position, and thus, is in motion. Follow the full article to understand the concept well.
What is the Position of an Object?
The true position of an object is its location, which is determined by the basic dimensions. The true position helps to control the variation of a specific feature from its desired position.
For example, the screw holes on a cylinder head cover must match the screw holes on the engine casing in size as well as position. In case they don’t, the two parts will not mate, and the lubrication oil for the valve assembly will leak out, defeating the purpose of the cover. The cylinder cover is useless, and a different piece must be used.
The Formula for the Position is Represented as:
Case 1:
\[\Delta x = x_2 - x_1\],
Where x1 is the first position of the body,
x2 is the second position after undergoing displacement,
And Δx is the rate of change in the displacement.
Case 2:
If the body changes its position after time t, the rate of change in position at any moment of time t, x(t), is articulated as
\[x(t) = \frac{1}{2} \alpha t^2 + v_0t + X_0\]
Where x(t) is the position of the body with time t,
x0 is the initial position of the body,
v0 is the initial velocity of the body, and
α is the acceleration the body possesses.
Example:
A boy who has an initial velocity of 2 m/s had already covered a distance of 10 m. If it has a constant acceleration of 2 m/s2, find the position of the boy at the end of 5s.
Ans:
Position of the boy = \[x(t) = \frac{1}{2} \alpha t^2 + v_0t + X_0\]
=½ x 2 x 25 + 2 x 5 + 10 = 45m
Tips for Preparation for IIT JEE
The exam is competitive because lakhs of students appear every year, but with the right guidance and organized preparation, even you can clear this exam. Some of the tips that our experts give to the aspirants are as follows:
Knowing the syllabus well is the first step, get a printout of the syllabus and try to remember all the topics and subtopics mentioned in the syllabus.
Deciding on your study material; you should not confuse your mind by referring to too many sources for a single topic. Identify your source and stick to one source for one topic. You can check out the study materials provided on the website.
Have a clear idea about the marks allocation to every topic. We have already done that for you. Go through these before you start off your preparation.
Read the topics from the notes on your own once, and watch the related videos to grasp the concept better.
Simultaneously, start practising the past year's JEE papers and other sample papers. Compare and learn from the solution of these papers prepared by our subject experts.
Keep practising and keep revising the notes, make your own short notes for quicker revision.
Interact with the mentors to get regular feedback, support, and guidance to keep you on track.
Nobody can stop you if you keep following the process with sincerity and dedication.
FAQs on Position Formula
1. What is displacement?
In terms of physics, displacement is the shortest distance travelled by any object. For example, if X travels 15 m west, then 10 m north, again 15 m east, and 5m north, then the distance travelled by X is 45 meters. However, the displacement is only 5 m, which is the change of the position of X from its original position.
It is written as a change in the position of an object, that is, Δx = x0 - xf,
Where x0 is the initial position and xf is the final position.
Understanding displacement is important to understand the concept of the position formula.
2. What is the meaning of zero position tolerance?
Let us understand the concept with the help of an example. Let us have two holes with a position tolerance of 0.3 and a maximum material condition of 10.5. So, we have a virtual condition, that is,
VC = MMC - GTV
VC = 10.5 - 0.3 = 10.2.
Now, if the hole size is 10.3 with a positional error of 0.1, the part is still functionally acceptable because the VC would still remain 10.2.
However, due to drawing intent, the hole size is lesser than the lower limit, that is, the hole size is 10.3, but the lower limit is 10.5. The part would be rejected.
To avoid such rejection, the concept of zero tolerance is used. So, remove the position tolerance of 0.3 and replace it with zero tolerance, thereby reducing the chances of rejection and increasing efficiency in the manufacturing sector.
3. What is the meaning of concentricity?
Concentricity is a tolerance that controls the central axis of the referred object to a datum axis. It can be measured under the following conditions:
The center point of two or more circles should be one.
The median point of all opposed elements of a surface of revolution is congruent with a datum axis.
It is difficult and expensive to measure the concentricity of an object.
