Calculating Impact Force

Original post by majmuh24

Hi guys, and thanks for reading :smile:

In my engineering lessons, I am trying to calculate the force required to crush a plastic bottle and this process involves dropping weights on the bottle to see how much force is required to crush it.

Is there a way to measure the impact force of the weight upon contact with the bottle if it is dropped from a known height?

Posted from TSR Mobile

In short. No.
The magnitude of the force will depend on how the weight was decelerated on impact.
Unless you are going to measure the amount of crumple or the time taken to stop the weight.
I don't see the point. Why are you dropping the weight? Why not just place it on the bottle and let its actual weight act?
Your method seems odd.

(edited 10 years ago)

Reply 2

OP

Original post by Stonebridge

In short. No.
The magnitude of the force will depend on how the weight was decelerated.
Why are you dropping the weight? Why not just place it on the bottle and let its weight act?
Your method seems odd.

I tried I that way, but the jig made is unstable and tends to tip over when lots of weight is placed on it, so it has to be dropped.

I tried using this method, but the tray just tips over and doesn't doesn't stay level meaning not all of the force is acting on the bottle, so do you have any other ideas :s-smilie:

Thanks for the help :biggrin:

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Reply 3

Why not use a standard spring meter? (Force gauge?)

Reply 4

OP

Original post by Stonebridge

Why not use a standard spring meter?

Ah right, didn't think of that :tongue:

Do you mean the standard Newton meters, although I can't see how that would work :s-smilie:

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Reply 5

Original post by majmuh24

Ah right, didn't think of that :tongue:

Do you mean the standard Newton meters, although I can't see how that would work :s-smilie:

Posted from TSR Mobile

The usual gauges can measure both stretching or compression forces.
Can't really say how it would work for you without knowing your setup and exactly how you are doing this.

Anyway, if this is an engineering assignment, isn't the point of the exercise that you figure this out for yourself. :smile:

Reply 6

OP

Original post by Stonebridge

The usual gauges can measure both stretching or compression forces.
Can't really say how it would work for you without knowing your setup and exactly how you are doing this.

Anyway, if this is an engineering assignment, isn't the point of the exercise that you figure this out for yourself. :smile:

Right, my current set up is to use a jig that consists of two wooden plates held together by metal supports through holes drilled through each of these plates, but my problem is that the hole for the bottle is too big so it slips around, the holes for the supports are too big so it isn't well balanced and that the surface is too small to place large amounts of weights on there.

Not in this case, the original method was given by my teacher but I wanted to do it a different way as I felt that this method was inaccurate and could introduce measuring errors, but all the equipment is offered by the school so we aren't allowed to build our own stuff :frown:

TBH, I dont think my school has one of these, can you use the data logger things to do this?

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Reply 7

Original post by majmuh24

Right, my current set up is to use a jig that consists of two wooden plates held together by metal supports through holes drilled through each of these plates, but my problem is that the hole for the bottle is too big so it slips around, the holes for the supports are too big so it isn't well balanced and that the surface is too small to place large amounts of weights on there.

Not in this case, the original method was given by my teacher but I wanted to do it a different way as I felt that this method was inaccurate and could introduce measuring errors, but all the equipment is offered by the school so we aren't allowed to build our own stuff :frown:

TBH, I dont think my school has one of these, can you use the data logger things to do this?

Posted from TSR Mobile

You need to speak to your teacher again. It's impossible to give specific advice without seeing the equipment and what you are trying to do.

Reply 8

OP