Calculating Horsepower/Torque from Acceleration/Mass

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The discussion focuses on calculating horsepower and torque from acceleration and mass using kinetic energy formulas. The user presents their calculations for three samples of a vehicle's speed and attempts to convert kinetic energy into horsepower, but their results differ significantly from expected values. A suggestion is made to plot a graph of horsepower over time based on the sampled data, emphasizing the importance of accurate unit conversions. The conversation highlights the need for clarity in the data used for calculations, particularly regarding the vehicle's weight and time intervals. The user seeks assistance in identifying errors in their calculations to reconcile the discrepancies.
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Apologies in advance if this is not the correct forum.

This is (what seems to me) an old question people have been playing with for a while, but I don't seem to be able to figure out where I have gone wrong.

Could someone point out the mistake in my math from the following example:

Constant Mass = 1180Kg

Sample 1 @ 2 secs
Kilometers/Hour = 37
Meters/Sec = 10.278
RPM = 3000

Sample 2 @ 3 secs
Kilometers/Hour = 46
Meters/Sec = 12.778
RPM = 3780

Sample 3 @ 4 secs
Kilometers/Hour = 59
Meters/Sec = 16.389
RPM = 4860


Using the formula: KE = (1/2)(m)(v^2) I calculated

KE1 = 0.5 * 1180 * (10.278 * 10.278) = 62326 ??Joules??
KE2 = 0.5 * 1180 * (12.778 * 12.778) = 96333.6 ??Joules??
KE3 = 0.5 * 1180 * (16.389 * 16.389) = 158473.6 ??Joules??

Using the formula: W = (KE / Time) given the sampling time is 1sec
W = KE.

Converting (roughly) from W (watts) to HP: HP = W / 746

HP1 = 83.54
HP2 = 129.12
HP3 = 212.32

I know from another piece of software that the correct values should be:

HP1 = 59
HP2 = 76
HP3 = 105


Could someone be kind enough to point out my fault. Greatly appreciated.

Tony
 
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Could you start by stating the question exactly as it is given please.

~H
 
The question is:

Plot a graph showing horsepower at given time intervals based on sampled data.There are actually 10 samples, but I have only included 3 for simplicity. The original data only included Time, Kilometers/Hour and RPM (although I don't think RPM is needed for this part of the question). I converted KPH to meters/sec as I think this is the correct unit for KE.
 
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And you have no other information regarding the vehical?

~H
 
I was given the vehicle weight of 1180kg, and the time-sampled data, but nothing else.
 

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