Calculating Power of a Light Bulb

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SUMMARY

A 100-watt light bulb consumes 360,000 Joules of energy per hour, calculated using the formula 1 watt = 1 Joule/second. To equate this energy to kinetic energy for a 70-kg person, the kinetic energy formula (KE = 1/2 mv²) is applied. The resulting calculation indicates that the velocity required for the person to match this energy is approximately 101.43 m/s, derived from the equation 5142.86 m²/s². The discussion clarifies that taking the square root of the kinetic energy value will yield the necessary speed, confirming that the square root operation affects both the numerical value and the units.

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Jim4592
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Homework Statement


How many Joules of energy does a 100 watt light bulb use per hour? How fast would a 70-kg person have to run to have that same amount of kinetic energy?


Homework Equations


How fast would a 70-kg person have to run to have the same amount of kinetic energy?


The Attempt at a Solution



1 watt = 1 J/S so... 100 J/S * 3600s = 360,000 J

360,000 kg m^2/s^2 ÷ 70 = 5142.86 m^2/s^2

my only question would be do you just square root the value and would it remove both ^2?
 
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Yes a sqrt() acts on the units as well as the number
I think you are missing a factor 2 somewhere, ke = 1/2 m v^2
 
ok thanks for your help, I'm pretty sure i can handle it from here.
 

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