Just a few thoughts…
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climbon wrote:
Yoda-x wrote:
Since AMT uses an elastic band to increase acceleration you hit the ground at greater velocity from a given box height. Isn’t that the same as increasing the box height?[/quote]
Yep. Higher box = longer time exposed to the force of gravity = greater velocity upon impact = greater force of impact and since F=MA if F increases and M stays the same then it is has the net effect of increasing acceleration or decelleration value as it were.
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You’ll still hit the ground at greater velocity. Would it be the same to jump off a lower box with bands (AMT) and a box at a height that would allow you to achieve the same velocity upon hitting the ground?[/quote]
Yes it would. The only caveat is that when bands are used you can continue to deliver force even after velocity components are zero or after landing even if it is only a fraction of a second. It is my understanding that the bands are released by an observer upon seeing impact. Reaction times are going to give another .3-.5seconds of force application due to the delayed release.
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No because that breaks the laws of physics.[/quote]
Which law is broken?
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The speed at which you are falling is the speed of gravity.[/quote]
Gravity is a measure acceleration not speed.
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Changing the height of the box does not change the speed of gravity.[/quote]
It doesn’t change the acceleration of gravity but it changes the speed of the object by increasing the time that acceleration can be applied. Jump off your chair, then jump off your roof and see what changed.
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The bands increase velocity or acceleration and would be needed at each box height to achieve the desired effect.[/quote]
Bands apply an additional force on our mass; which is the same as having a greater force of acceleration. But what we are really after is a greater terminal velocity upon impact to elicit a greater force of impact and resultant force absorption among other things.
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F=ma: Mass is our bodyweight;[/quote]
Mass is our mass, weight has gravity factored in already. Mass is generally measured in Kgs, the pound is a measure of mass under earth’s gravity
Acceleration = force / mass
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You can increase force by adding weight which will increase the mass, but acceleration will remain at the speed of gravity.[/quote]
And the net result is greater force of impact as long as the weights are held during impact but I think that negates the purpose of the AMT jumps since one would have to reaccelerate the extra load instead of just ones bodyweight.
Yes.
So how is that different from jumping off a higher box? Don’t you also end up with a higher force of impact and only have to reaccelerate your bodyweight?
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Both options are valid, but the effect is a little different since either mass or acceleration are changed. That is why I posted earlier that you would not get the same result trying to perform AMT jumps holding dumbbells. The dumbbells would increase force but the result would not be similar to AMT jumps that are increasing acceleration.[/quote]
I think you have a good point about the dumbells being an inferior option for the reasons that I stated earlier but why not just use a higher box to elicit the same effects as AMT jumps?
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Again, I am not an expert in physics and I may not be entirely correct in my explanation. If not, I apologize and ask for someone to correct me.[/quote]
I’m not an expert either but I am pretty sure my reasoning is valid. And if it isn’t I’m sure someone will correct me ;).
I don’t think there is any difference between using a band or additional drop height to increase terminal speed of an object in the direction of the force of gravity. Velocity is a measure of speed and direction. And it may be the case that bands alter the direction of terminal velocity of an object, resulting in a change in the acceleration component which is different from gravity since it only acts perpendicular to the earth’s surface. But I think this is splitting hairs…
I think AMT jumps sound really cool and exotic but as far as physics is concerned it would be the same as stepping off a higher box or merely adding a jump up off the box of the same height. Eller hur?