Calculate height and velocity given kinetic and potential?

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To calculate height and velocity from given potential and kinetic energy values, use the equations PE = mgh and KE = 1/2mv^2. If mass is not provided, height can be expressed as a function of mass, such as h = PE/(mg). For cases where kinetic energy is zero, velocity can be determined directly from the conservation of energy principle, linking different states of the same object. The discussion emphasizes the importance of understanding energy conservation to fill out the table correctly. Applying these principles allows for solving the height and velocity even without a specific mass value.
JohnDoe624
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Homework Statement


I have a table that needs to be filled out. In each column, potential and kinetic energy are given, but height and velocity are left blank. Ex: PE = 20 J, KE = 0 J, h = ?, V = ?

Homework Equations


KE = 1/2mv^2
U = mgh

The Attempt at a Solution


I'm totally stumped. How can I figure out either of these with no mass given?
 
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Could you simply write height as a multiple of mass?
i.e. if PE = 20J ##h = \frac{20}{9.8 m} ## where m is in kg.
 
Forum rules require you to post the question word for word.
JohnDoe624 said:
KE = 0J ... V = ?
You should be able to do that one.

As for the other entries in the table... Do they relate to the same object at different times? Perhaps try applying conservation of energy between two rows in the table.
 

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