Getting confused on how to determine which equation to use?

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The discussion centers on understanding how to select the appropriate Kinetic Motion equations related to velocity and acceleration. Participants suggest creating a chart to identify present variables and those needed for solving problems. Despite this advice, some users express difficulty in extracting variables from problems. A sample problem is provided to illustrate how to identify variables like initial velocity, final velocity, and time. Practice and familiarity with various problems are emphasized as key to improving equation selection skills.
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So we are talking about velocity and acceleration, as well as the Kinetic Motion equations. Everyone is saying to make a chart, if you will, seeing which variables are present and which one you need. They say this will help you in picking an equation. However, I am still really having a hard time in picking the variables out of a problem...Does anyone have any tips or maybe a sample problem that you could pick the variable out of so I could see a sample?

Thank you so much!
 
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emlekarc said:
So we are talking about velocity and acceleration, as well as the Kinetic Motion equations. Everyone is saying to make a chart, if you will, seeing which variables are present and which one you need. They say this will help you in picking an equation. However, I am still really having a hard time in picking the variables out of a problem...Does anyone have any tips or maybe a sample problem that you could pick the variable out of so I could see a sample?

Thank you so much!
I think you need to get a feel for it. You can do this best, in my opinion, by working lots of problems. Nothing beats experience and practice.

Chet
 
emlekarc said:
So we are talking about velocity and acceleration, as well as the Kinetic Motion equations. Everyone is saying to make a chart, if you will, seeing which variables are present and which one you need. They say this will help you in picking an equation. However, I am still really having a hard time in picking the variables out of a problem...Does anyone have any tips or maybe a sample problem that you could pick the variable out of so I could see a sample?

Thank you so much!
Its so easy,for example,:
A car initially traveling with a velocity of 100m/s comes to rest in 30s.
What is the distance traveled during this time?

The variables here are initial velocity,final velocity and time so you can use ##S=\frac{1}{2}(u+v)t##
Try to write all the equations and find the one with all the variable in question.
 
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