Is the Equation X=ut+1/2at^2 Homogeneous with Respect to Units?

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Homework Help Overview

The discussion revolves around the equation X = ut + 1/2at² and its homogeneity with respect to units. Participants are exploring the implications of this equation in the context of uniformly accelerated motion and the use of graphs to analyze acceleration and distance traveled.

Discussion Character

  • Conceptual clarification, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the definition of homogeneity in relation to units and suggest comparing the units of each term in the equation. Some express uncertainty about the term "homogeneous" and attempt to relate it to differential equations. Others inquire about using a velocity-time graph to determine acceleration and distance traveled.

Discussion Status

There is an ongoing exploration of how to demonstrate the homogeneity of the equation with respect to units. Some participants have provided potential approaches, such as comparing units and analyzing graphs, while others express confusion about the concepts involved. The discussion reflects a mix of interpretations and attempts to clarify the problem.

Contextual Notes

Some participants mention specific constraints, such as the need to analyze a graph showing speed over time and the requirement to determine the magnitude of acceleration and distance traveled within specified time intervals. There is also a reference to the participants' varying levels of familiarity with calculus, which may impact their understanding of the problem.

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DEMONSTARTE THAT THE EQUATION X=ut+1/2at2(squared) is homogeneous with repect to units?
how can i use a graph with a streight diagnal line to determine magnitude of acceleration?
 
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faisal said:
DEMONSTARTE THAT THE EQUATION X=ut+1/2at2(squared) is homogeneous with repect to units?
Take each term in that equation and plug in standard units for each variable. Then simplify and compare with each other. (They better all end up with the same units!)
how can i use a graph with a streight diagnal line to determine magnitude of acceleration?
For uniformly accelerated motion, a graph of v (velocity) vs. t (time) will be a straight line whose slope will be the acceleration.
 
I'm not too sure what you mean by homogeneous with respect to units so I'll use the definition for when an ordinary differential equation is homogeneous. Sorry but I don't know TeX too well so try and bear with me as I try to answer this without:

Writing the above equation in differential form, you get

X = dx/dt * t + 1/2 * d^2 x/(dt^2) * t^2

Because all the terms are proportional to X (or one of its derivatives) and beacuse there are no terms without some form of X in them, it is homogeneous.

Edit: nevermind :) Compare units of both sides.

As for the acceleration, you can find the magnitude of the acceleration by taking the instantaneous slope of a velocity-time graph. This graph will be a straight line if acceleration is constant so the slope would be the acceleration.
 
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As for the acceleration, you can find the magnitude of the acceleration by taking the instantaneous slope of a velocity-time graph. This graph will be a straight line if acceleration is constant so the slope would be the acceleration.
the diagram shown in the question is a speed/time graph which shows a constant slope, i don't know how to address this problem?i don't know how to determine magnetude acceleration,
this is what the question states
a graph shows the speed of a body during time intervals or just over 3 seconds,
(theres a diagram of a small graph with from 0-8ms-1 on the y-axis and 0-8s on the x axis, the graph also shows a slope which appears to be constant.
the question tells me to determine the magnetude of the acceleration?
and to find the distance traveled by the body, between t=6 and t=8.
i'm really struggling.
 
A = change in velocity / change in time . It doesn't really matter which two points you use to calculate the slope since it's linear. Are you currently taking calculus? These problems are trivial if you have at least Calc I under your belt. The position can be determined from a velocity-time graph by taking the area between the time axis and the graph between the two time intervals you said.
 

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