Force of Impact

[sciencedummy]

I was reading another topic on something like this by budullewraagh... but i want to change the circumstances where:

 

if there is an object with a mass of, say, 80kg traveling at a rate of 50m/s, hypothetically, and it hypothetically crashes into a wall, would you happen to know, offhand, the force of impact? the object stops after it hits the wall.

 

I was reading about F=ma and E=1/2mv^2, but im not sure how that would work.

[swansont]

I was reading another topic on something like this by budullewraagh... but i want to change the circumstances where:

 

if there is an object with a mass of' date=' say, 80kg traveling at a rate of 50m/s, hypothetically, and it hypothetically crashes into a wall, would you happen to know, offhand, the force of impact? the object stops after it hits the wall.

 

I was reading about F=ma and E=1/2mv^2, but im not sure how that would work. [/quote']

 

As was discussed in the "f=ma" thread, this requires knowing the time it takes for the object to come to rest. F= dp/dt, and for average values, you can replace the derivatives (d) with "change in" or delta. So the mv/t is the average force

[sciencedummy]

does this mean F=mv/t? to find impact force?

 

what if you went ahead to use Ek=1/2mv^2 to find the kinetic energy, would that relate to the impact force or would that be totally irrelevant.

[swansont]

does this mean F=mv/t? to find impact force?

 

what if you went ahead to use Ek=1/2mv^2 to find the kinetic energy' date=' would that relate to the impact force or would that be totally irrelevant.[/quote']

 

The kinetic energy would be useful if you knew the distance over which the object came to a stop. KE=Work=Fd

[sciencedummy]

so if i had the distance, i would find acceleration and then i could find force...

 

what would the kinetic energy represent tho

in accordance with hitting the wall?

[swansont]

so if i had the distance' date=' i would find acceleration and then i could find force...

 

what would the kinetic energy represent tho

in accordance with hitting the wall?[/quote']

 

If you look at the equation, the KE/distance gives you the average force directly.

 

KE would correspond to the...energy. It all would get dissipated in heat, sound and deformation.

[sciencedummy]

ok, so work is the transfer of energy, the object applies a force through the distance... would the distance be the distance the object travels before hitting the wall? but in the end the object does not penetrate through the wall, so can it be said that the object covered no distance?

 

but if that is the case then there is no work and there is no kinetic energy.

[swansont]

ok' date=' so work is the transfer of energy, the object applies a force through the distance... would the distance be the distance the object travels before hitting the wall? but in the end the object does not penetrate through the wall, so can it be said that the object covered no distance?

 

but if that is the case then there is no work and there is no kinetic energy.[/quote']

 

If the object is moving there is kinetic energy. The object's center of mass will have to move some distance during the impact.

[J.C.MacSwell]

If the object is moving there is kinetic energy. The object's center of mass will have to move some distance [/b'] during the impact.

 

Yes, otherwise the force required would be infinite which of course is not possible.