# Physics in sports

1. Jan 15, 2008

### koprox

1. In bowling, is it better to use a lighter ball than a heavier ball?

--- I'm guessing it's better to use a heavier ball because mass is directly proportional to momentum. Is this correct?

2. In billiards, what are the strategies in making a good break?

3. What is the winning strategy for an egg-catching game using raw eggs so it won't break? What is the relevance of the momentum-impulse theorem?

--- Those other two, though, I have no idea.

2. Jan 15, 2008

### WiFO215

Not necassarily. If its a lighter ball the same amount of force can send the ball going faster. If its a heavier ball it will be slower. For the same amount of force provided it doesnt matter upon its mass.

3. Jan 15, 2008

### blochwave

Well ever try and catch an egg? *chucks an egg at you* what's gonna happen if you just reach up and snatch it like a baseball? Asplode. What do you HAVE to do to avoid this? The point of the impulse theorem that you wanna use here is that the longer it takes you to change something's momentum, the less force is being applied

For the first one you forget that its velocity is also directly proportional to momentum. If you can throw a ball with half the mass twice as fast it'll have the same momentum. But CAN you? Assuming you're throwing the ball as hard as you can both cases, you have to do work on it and you're gonna give it the same energy each time, so think about it with your kinetic energy equation

4. Jan 15, 2008

### rohanprabhu

There are two key ideas to be followed here. First one is that, force is the cause of breakage. Second thing is that, force is the rate of change of momentum. Since, momentum is the product of mass and velocity, and mass won't change [i'll kill the person who cries 'relativity'], we can say that the force is directly proportional to the change in velocity.

So, lesser force will be applied if the the velocity is brought down to 0 over a longer period of time. So, the best strategy would be to swing the basket in the direction of the egg while catching it. It's difficult to explain in words, but take the case of a baseball player. If a baseball player is to catch a ball, he preferably swings his hands after catching the ball [or when the ball just enters his hands] in the direction the ball was thrown. What he basically does is, he keeps the ball in motion for a small period of time before bringing it to 0. This motion needs to be smooth so as to prevent a high value of acceleration. The same applies to the egg-catching game...

EDIT:
blochwave got here 1 minute earlier...:grumpy:

Last edited: Jan 15, 2008