Solving Kinetic Energy Lab in Online Physics Class

AI Thread Summary
The discussion revolves around challenges faced in a physics lab focused on kinetic energy and kinematic equations. The user struggles with calculating kinematic velocity and kinetic energy due to confusion over the relevant equations and the mass of the object used in the experiment. It is clarified that kinetic energy does not depend on mass, as it cancels out in the equation. The correct formulas for calculating velocity and kinetic energy are provided, emphasizing the importance of unit consistency. Overall, the conversation aims to assist the user in completing their physics lab successfully.
McSara
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I'm having some difficulty in an online class.
Here is a screen shot for reference:
Picture1-12.png


Homework Statement

:
I'm doing a physics lab (screen shot is available above). The procedure says:
Choose a set height (2 feet, 3 feet) and when the object is dropped from this height, start the time. Stop the time, when the object hits the ground. Calculate the velocity of the object. Calculate the average velocity for each equation at the end of your experiments.
The small object I'm using is a small pecan in it's shell.
As you can see from the screen shot I have already recorded the time column from the experiment.
I'm having a difficult time with kinematic velocity (because I don't understand the equation) and the kinetic energy (because the KE formula asks for mass and I do not know the mass of the almond. This lab was not specific to mass, only specific of using a small object. More specifically it says: to use a "small object (thread spool, small ball)")


Homework Equations

:
Kinematic velocity = v0 + acceleration*time
Kinetic Energy = ½mv^2 = mgh


The Attempt at a Solution

:
I don't know how to go about either one of these. I'm sorry. The book is confusing me, too.
 
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Welcome to PF.

One thing should make it easier for you.

The kinetic energy V doesn't depend on mass. If you will note it cancels out of both sides of the equation.

Hence your kinetic V is (2*g*h)1/2
Your kinematic V is simpler and is just g*t

Be careful of your units. 1 column is m/s. The other is ft/s.
 
Welcome to PF!

McSara said:
I'm having a difficult time with kinematic velocity (because I don't understand the equation) and the kinetic energy (because the KE formula asks for mass and I do not know the mass of the almond. This lab was not specific to mass, only specific of using a small object. More specifically it says: to use a "small object (thread spool, small ball)")

Kinematic velocity = v0 + acceleration*time
Kinetic Energy = ½mv^2 = mgh

Hi McSara! Welcome to PF! :smile:

It isn't kinematic velocity, it's a kinematic equation.

v is just ordinary velocity. :wink:
 
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