Calculating Kinetic Energy of Meteor

AI Thread Summary
The kinetic energy of a 1g meteor traveling at 30,000 m/s is calculated using the formula KE = 1/2 MV^2, resulting in 450,000 Joules. There is a common misconception that the mass should be multiplied by 4 when the velocity is squared, but this is incorrect. The mass should simply be used as is in the formula without any additional multiplication. The one-half factor in the equation is separate from the squared velocity term. Understanding the correct application of the kinetic energy formula is crucial for accurate calculations.
vandorin
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Homework Statement



What is the Kineti energy of a 1g (0.001kg) meteor traveling at 30,000m/s? Express your answer in Joules.

Homework Equations


KE=1/2MV^2


The Attempt at a Solution


1/2(.001kg)(30,000)^2 = 450000J


Now since 30,000 is squared, would i have to multiply .001kg by 4, before i did all of this math?
 
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Nope. You just plug .001kg in for M. Out of curiosity, why would you multiply by 4?
 
I thought that since v is squared, you had to multiply the mass by 4...or is that only if its 2v^2?
 
vandorin said:
I thought that since v is squared, you had to multiply the mass by 4...or is that only if its 2v^2?

Nope, the one half is a separate term from the squared term:

KE = (1/2) * (m) * (v2)
 

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