golf ball v egg
Author
Hi,
Imagine a golf ball and an egg fired directly towards each other at say 500mps.
They are of equal mass, and both intact just before the collision. Now, I think its pretty certain the egg will smash into tiny pieces while the ball is unscathed, but what will the speed of the golf ball be and in which direction after the collision (assume no gravity)?
Will the golf ball just go through the egg taking relatively little speed loss, or, because they are equal mass, will the golf ball slow down to almost stationary because the momentum of the egg has slowed it down regardless of the fact the egg got smashed?
Thanks,
Yratelev
That depends on so many variables that it almost makes the question meaningless.
Are the objects spinning? At what orientations are they when they collide (An egg being ovoid is stronger at some points than others)? What sort of egg is it (size, mass, shell thickness, sheer strength of shell, is it hard boiled, what shape is it) What is the mass of the golf ball? How is it constructed? What material is it? Is it an old fashioned leather golf ball? Do they hit each other perfectly central?
All you can really say is that if the egg does break (which is not certain), then the golf ball will be slowed by some factor and would most probably also be defelected in some way.
Are the objects spinning? At what orientations are they when they collide (An egg being ovoid is stronger at some points than others)? What sort of egg is it (size, mass, shell thickness, sheer strength of shell, is it hard boiled, what shape is it) What is the mass of the golf ball? How is it constructed? What material is it? Is it an old fashioned leather golf ball? Do they hit each other perfectly central?
All you can really say is that if the egg does break (which is not certain), then the golf ball will be slowed by some factor and would most probably also be defelected in some way.
Author
Quote:Original post by Anonymous Poster
That depends on so many variables that it almost makes the question meaningless.
Are the objects spinning? At what orientations are they when they collide (An egg being ovoid is stronger at some points than others)? What sort of egg is it (size, mass, shell thickness, sheer strength of shell, is it hard boiled, what shape is it) What is the mass of the golf ball? How is it constructed? What material is it? Is it an old fashioned leather golf ball? Do they hit each other perfectly central?
All you can really say is that if the egg does break (which is not certain), then the golf ball will be slowed by some factor and would most probably also be defelected in some way.
I really cant believe someone posted that. Dude, its an egg and a golf ball, two everyday objects that I put in to make the problem seem easier to digest. Make whatever assumptions you feel nessacary.
Yratelev
It all depends on the mass ratios of the two objects, the hardness of the bodies, and the size. Seems the masses are closed to each other the egg has sufficient momentum to deflect the ball even thought lot of it be dispersed on the component of the egg flying apart. However a good part of these components will still be hitting the ball in direct collision.
This question is similar to what cases more damages a solid asteroid hitting a planet or one that was pulverized but an explosion, they both cause the same damage.
This question is similar to what cases more damages a solid asteroid hitting a planet or one that was pulverized but an explosion, they both cause the same damage.
Quote:Original post by Yratelev
Now, I think its pretty certain the egg will smash into tiny pieces while the ball is unscathed
If the egg's longest axis was in the direction of travel and it was spinning, I don't think I'd want to place any bets on that one.
Of course, that's a *big* if :)
EDIT: Oh, and in answer to your question, it would go left.
Irrespective of what happens to the egg you'll likely have to drop a shot and play from the spot it landed in making any chance of hitting the green on your next shot unlikely.
No seriously, when the two collide the force acting upon the egg from the golf ball will be larger than that acting the other way. The exchange of energies will see some spent in blowing the egg apart and some on noise, the remainder will simply slow the gold ball down slightly.
Think of it like this: when my go kart, rolling on a flat surface, hits my friend I experience a thump and I'm thrown forward in the seat slightly but continue onwards with a worried look on my face. However as I continue on I'm struck by a bus coming the other way. It makes a mess of my worried looking face and I end up carried backwards by the bus. The bus will have suffered a slight drop in speed but it will have been tiny as the energy exchange is dependent upon the mass of the objects involved (and the rigidity in the case of the egg).
Hope that helps.
No seriously, when the two collide the force acting upon the egg from the golf ball will be larger than that acting the other way. The exchange of energies will see some spent in blowing the egg apart and some on noise, the remainder will simply slow the gold ball down slightly.
Think of it like this: when my go kart, rolling on a flat surface, hits my friend I experience a thump and I'm thrown forward in the seat slightly but continue onwards with a worried look on my face. However as I continue on I'm struck by a bus coming the other way. It makes a mess of my worried looking face and I end up carried backwards by the bus. The bus will have suffered a slight drop in speed but it will have been tiny as the energy exchange is dependent upon the mass of the objects involved (and the rigidity in the case of the egg).
Hope that helps.
Oh, come now, surely we can actually answer at some point?
Both parts have energy and momentum. Momentum will be conserved. Energy will be lost. Unfortunately some momentum will be retained by remnants of the egg, but we have limits - we know the golf ball will change momentum and energy by at least 0 and at most the momentum/energy of the egg.
I would say forget elasticity, give the egg a 'splat' coefficient, between 0.0 and 1.0, assume a totally inelastic collision, and then multiply the resulting change in velocity of the golf ball by the splat coefficient. An egg with a high splat value will immediately splat and have no effect. An egg with a very low splat coefficient will only just break and deflect the golf ball quite significantly.
This branch of phsyics (aka the splat approximation) is atleast as valid as the rigid body mechanics approximation in this case. The only thing you might try is multiplying the change in energy by the splat, instead of the change in momentum (v^2 instead of v).
Both parts have energy and momentum. Momentum will be conserved. Energy will be lost. Unfortunately some momentum will be retained by remnants of the egg, but we have limits - we know the golf ball will change momentum and energy by at least 0 and at most the momentum/energy of the egg.
I would say forget elasticity, give the egg a 'splat' coefficient, between 0.0 and 1.0, assume a totally inelastic collision, and then multiply the resulting change in velocity of the golf ball by the splat coefficient. An egg with a high splat value will immediately splat and have no effect. An egg with a very low splat coefficient will only just break and deflect the golf ball quite significantly.
This branch of phsyics (aka the splat approximation) is atleast as valid as the rigid body mechanics approximation in this case. The only thing you might try is multiplying the change in energy by the splat, instead of the change in momentum (v^2 instead of v).
Well, hm.
An introductory college physics textbook would try to shoehorn this as a "perfectly inelastic collision". Two bodies flying through space hit and stick to each other. Momentum is conserved, so the final velocity vector is v = (v1*m1 + v2*m2)/(m1+m2). For equal masses and opposite velocities, that means zero.
In this case, however, the situation may be different. If the golf ball hits the egg on a side, it's likely that the shock wave produced in the egg would act to split the egg in half, the pieces flying around the egg but not (for the most part) adhering. In this case, there would be significant speed loss, but both the golf ball and the egg would still be flying quite fast. The exact numbers, of course, depend on quite a lot of variables.
An introductory college physics textbook would try to shoehorn this as a "perfectly inelastic collision". Two bodies flying through space hit and stick to each other. Momentum is conserved, so the final velocity vector is v = (v1*m1 + v2*m2)/(m1+m2). For equal masses and opposite velocities, that means zero.
In this case, however, the situation may be different. If the golf ball hits the egg on a side, it's likely that the shock wave produced in the egg would act to split the egg in half, the pieces flying around the egg but not (for the most part) adhering. In this case, there would be significant speed loss, but both the golf ball and the egg would still be flying quite fast. The exact numbers, of course, depend on quite a lot of variables.
This topic is closed to new replies.
Advertisement
Popular Topics
Advertisement
