Golfer18 said:
Whats the equation for work?
Now we are talking bro!
This will settle this discussion with FACTS using laws of nature.
The equation for work is:
Work = F * s = m*g*s - In English: Weight * Gravity * Distance
If a person lifts 100 kg 1 meter he uses:
100 kg * 9,82 * 1,0 meter = 982 Nm = 982 Joule
This is called potential energy.
Compared to a person with short arms, who only lifts the weight 0.8 meter, the equation looks like this.
100 kg * 9.82 * 0.8 = 786 Joule
As seen, the change in energy used is in proportion with the distance you have to lift your weight.
But to find out the total MECHANICAL energy used one would have to add the kinetic energy used (energy from movement/speed).
Total Energy = Kinetic E + Potential E
KineticE = (mv^2)/2
Lets say that it takes one second to lift the weight the distance 1.0 meter, the equation would look like this.
(100 kg * 1.0s^2)/2 = 50 Nm = 50 Joule
Total Energy = 982 Joule + 50 Joule = 1032 Joule
To test how much speed affects the energy used lets test a different number. Lets do a 2.0 sec lift.
(100 kg * 2.0s^2)/2 = 200 Joule
Hereby we understand that - If you double the time used you quadruple your kinetic energy.
But the Total Energy used isn't affected "that" much by speed as by pure weight.
Total Energy = 982 Joule + 200 Joule = 1182 Joule.
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To sum it up easy. Using the formula:
Total Energy used = Kinetic Energy + Potential Energy
Is an short and easy explanation. But in comparision with what we are looking for quite near the truth. One could add extra numbers from acceleration, etc etc etc. But these two energy together is enough to prove a point.
1. The BIGGEST differance in who does the heviest work is DISTANCE the barbell/dumbell travels!!!!
2. One can't forget about how fast one moves the weight. In numbers it isn't as relevant as distance, but it makes a differance. Small? yes! But, enough to determine wether you lift the attemted weight or not!
NOTE: This is extremly importante! You can NOT use lbs or feet/inches/yards in these equations. The reason for this is that the equation is based on metric standards, sorry bro's!!!
But do use these ones -->
1 kg = 0.454 lbs
1 m = 39.4 inches
example: m g s = (100lbs/0.454) * 9.82 * (100inches/39.4)
Ok, this is a lot of mumbojumbo here,,, but Point 1 and 2 sums it up!!
PS: did I mention no one has ever given' me Karma =(