Recent content by paget

Another question: is it correct that the harder the surface of the two balls is the less long the impact would last and therefore the 'force of the impact' and the acceleratuion of the second ball would be higher?

I am glad that you have taken the time to show me how this could be calculated. again I was not looking for a concrete result, the only thing I wanted is to show a demonstration how it could be calculated by using fictional numbers.

so if we knew these two things we could calculate my example right? let's say the impact lasted 0.05s or the force was applied for 0.5mm.

There are still many things I don't understand but I would really like to. let's take a different example: person A weighs 50 kilograms and is sitting. person B stands behind and stares downwards at the top of person A's head. both have, instead of a human head, a billiard ball head that weighs...

One last question: Regarding the formula f=m*a, when we are looking for the peak force that affected the shelf, the peak mass that hits the shelf, m must be somewhere between 5(head) and 50(whole body)kg Is that correct? Or is the only way we could calculate the force through l =v*m?

Wow, great answer Sophie. You couldn't have explained it better! Thanks.

Nothing. My question was more theoretically. replusz and sophiecentaur have pretty much answered my question.

Okay I just noticed that my last post was nonsense, this would demonstrate as the force behind the impact not the actual 'mass' that hits Shelf. I'm sorry but I have huge problems explaining what i mean, I am not good at physics.

No Jbriggs. I think you misunderstood what I was trying to say. imagine that the shelf is a special scale. The hit would show us how many kg the impact had. This is the mass I would be looking for.

I am happy that you both understood what I meant. i am not looking for an exact calculation which is impossible anyway. So if a person weighs 50 Kilogramm, the mass that hits the shelf must be between 5(head) and 50(whole body) Kilogramm, is that correct? What I also do not fully understand...

Hello, imagine the following scenario: a persons sits and stands up. At mid- distance the person's hits the head on a shelf that is right above the head. A Human Head weighs about four Kilogramm. the question I have now is, what is the mass of the impact? is it exactly four kilogram or more...

So we have now 400 Newton and 32 joule, but still no G-Force?

There was a misunderstanding I meant that the skin deformed 5 and 8 millimeters ,not the ball. for the deformation of the ball and the skin we estimated 2cm (1.5 ball, 0.5 skin) I measured with a scale that the deformation of the ball of 1 centimeters requires 40 kilogram, this is as hard as I...

I appreciate all your help but you start to make things way too complicated for me now. I was never good at physics and I can't follow you anymore, sorry. reasonable estimations are absolutely sufficient for my caveat, like jbriggs was doing in the previous posts. otherwise this calculation...

sophie, I understand that the physics behind the impact are very complicated, but this calculation should just demonstrate a reasonable result, even it if varies from the actual event. I would say that the tennis ball moved 8 millimeters at maximum, and yes it did hurt.