Kinetic Energy from Velocity Vector

AI Thread Summary
To find the kinetic energy of a 3.00 kg object moving with a velocity vector of <6, -1> m/s, the correct method involves calculating the dot product to determine v-squared. The calculation yields v^2 = 37, leading to a kinetic energy of 55.5 J when multiplied by 3 and divided by 2. However, the textbook states the answer is 60.0 J, prompting confusion about the discrepancy. The discussion highlights that the problem does not specify a required degree of accuracy, suggesting the calculations are correct. The difference may stem from rounding or assumptions in the textbook's answer.
AdkinsJr
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I just need to find the kinetic energy of a 3.00kg object moving with a velocity <6,-1> m/s. I should be able to take the dot product to find v-squared right? I find that v^2=37, multiply by 3, divide by 2, this gives 55.5 J, the book says 60.0 J. I can't figure out what the problem is.
 
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Your answer matches the correct method. Did the question ask for a certain degree of accuracy?
 
rock.freak667 said:
Your answer matches the correct method. Did the question ask for a certain degree of accuracy?

No, it just gives the velocity vector, and asks for the kinetic energy.
 
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