Solving for Work: 14,500J Applied to 1.2m Crowbar

AI Thread Summary
Applying 14,500 J of work to a 1.2 m crowbar raises questions about the output work produced. The initial calculation attempts to multiply the work and distance, resulting in incorrect units (J m) rather than proper work units. The discussion emphasizes the principle of conservation of energy, suggesting that the output work should equal the input if no energy is lost to friction or other factors. Ultimately, the output work can be considered equal to the input work under these ideal conditions. This highlights the importance of understanding work and energy principles in physics.
NatalieWise123
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Homework Statement


You apply 14,500 J of work to one end of a crowbar. If the crowbar is 1.2 m long, how much work is produced by the crowbar? (friction is not a factor)

Homework Equations


Work=distance*force

The Attempt at a Solution


There's hardly any information in this question so the only thing I can think to do is multiply the two numbers. That would give you 1.74 x 104 J which would make the output greater than the input which isn't allowed, right?[/B]
 
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NatalieWise123 said:
There's hardly any information in this question so the only thing I can think to do is multiply the two numbers. That would give you 1.74 x 104 J
No, that would give 1.74 x 104 J m, which are not proper units for work.
NatalieWise123 said:
which would make the output greater than the input which isn't allowed, right?
Conservation of energy is indeed a good place to start.
 
DrClaude said:
No, that would give 1.74 x 104 J m, which are not proper units for work.
Conservation of energy is indeed a good place to start.

would the output just be equal to the input then?
 
NatalieWise123 said:
would the output just be equal to the input then?
Yes, if you can neglect any work done on the crowbar itself.
 
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