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The discussion centers on the calculation of kinetic energy (KE) for an object on Earth versus the Moon. The formula KE = 1/2 mv² indicates that kinetic energy depends on mass, which remains constant regardless of location. Therefore, the kinetic energy ratio of a body moving at speed V on Earth compared to the Moon is 1:1, confirming that the answer is C. The confusion arose from mixing up weight and mass, as weight is affected by gravitational acceleration.

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The weight of an object on the moon is one-sixth of its weight on Earth. The ratio of the
kinetic energy of a body on Earth moving with speed V to that of the same body moving with
speed V on the moon is:

A. 6:1
B. 36:1
C. 1:1
D. 1:6
E. 1:36

I did the calculations using KE = 1/2 mv2 and got A, but the answer is C. Any explanations? Thanks.
 
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Using KE = 1/2 mv^2 you would get the same answer on the moon as on Earth. The formula has MASS in it, not WEIGHT. The mass of an object is the same on the moon as it is on Earth. The weight, F = mg, is different because the gravitation acceleration g is less on the moon.
 
Wow, thanks for that! Such a silly mistake.
 

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