Potential energy and a skateboard, only have until 11:30

AI Thread Summary
The discussion revolves around calculating the change in gravitational potential energy for a skateboarder who experiences various forces while moving. To determine this change, the initial and final heights of the skateboarder are essential, but this information is missing from the scenario. Potential energy is linked to the skateboarder's height and can be converted into kinetic energy through motion. The conversation highlights the importance of height in maximizing potential energy before descending a ramp. Ultimately, without the height data, the calculation of potential energy change remains incomplete.
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Potential energy and a skateboard, only have until 11:30!

A 54.5 kg. skateboarder starts out with a speed of 1.95 m/s. He does +80.0 J of work on himself by pushing with his feet against the ground. In addition, friction does -265 J of work on him. In both cases, the forces doing the work are nonconservative. The final speed of the skateboarder is 6.10 m/s

Calculate the change (PE = PEf - PE0) in the gravitational potential energy

(b) How much has the vertical height of the skater changed?



ok so potential energy is PE=MGH buti don't see a vertical height here!

Please help!
 
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Hi, Welcome to PF!

Take a moment to read the first couple of threads (labeled "Stickies" )https://www.physicsforums.com/showthread.php?t=28

There are many people here willing to help, and you will find it to be everyone's benefit, if you post your problem in only one area.

Thanks

if anyone would like to respond to this question please go here:
https://www.physicsforums.com/showthread.php?t=65026
 


Hi there! It seems like there is some missing information in the given scenario. In order to calculate the change in gravitational potential energy, we need to know the initial and final heights of the skateboarder. Without this information, we cannot accurately determine the change in potential energy.

However, we can still discuss the concept of potential energy and how it relates to a skateboard. Potential energy is the energy that an object possesses due to its position or configuration. In the case of a skateboard, potential energy can be stored in the form of elastic potential energy in the wheels or potential energy due to the height of the skateboarder.

When the skateboarder pushes with their feet against the ground, they are doing work on themselves and increasing their kinetic energy. This means that the potential energy stored in the skateboard is being converted into kinetic energy, which is the energy of motion. Similarly, when friction does work on the skateboarder, it is converting some of their kinetic energy back into potential energy.

In order to maximize the potential energy stored in a skateboard, one can try to gain as much height as possible before going down a ramp or hill. This will increase the gravitational potential energy of the skateboarder, which can then be converted into kinetic energy as they go down the slope.

In conclusion, potential energy plays an important role in the movement of a skateboard and can be affected by various factors such as height, speed, and friction. However, without the necessary information, we cannot accurately calculate the change in potential energy in the given scenario. I hope this helps!
 
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