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so here I want to illustrate the

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difference between static and dynamic

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forces a static force or a static load

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is just the weight of an object this

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hammer here weighs 10 pounds when I put

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it on top of this can let it just sit

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there there's a static force going down

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which is just the weight it's the force

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due to gravity and there's an equal

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force that's holding this back up so

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there's 10 pounds going down here

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there's 10 pounds going back up here now

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I use soda cans like this because

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they're very strong I can support over a

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over a hundred pounds so here is

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supporting about one tenth of its actual

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actual load capacity now a dynamic force

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is the force that happens when something

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is moving and it hits something that is

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not moving and it has to either stop or

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go through that thing so in this case if

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I was to drop this hammer and if it was

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to land on that there's a force slowing

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down the hammer now that is a lot more

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than the actual force of 10 pounds of

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gravity this can can support a hundred

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pounds so if I was to drop this and it

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was to crush the can that means that the

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actual force is way more than 100 pounds

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so what I'm going to do is I'm gonna

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raise it up about two feet I'm gonna