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Phlaminghoe wrote:

Spacey wrote:Not true, unless you are saying there is not resistance due to wind.

When you are driving down the highway at 100, or a street at 60 ask your passenger to throw a tennis ball directly ball into the air... see what happens. Make sure there is no one behind you before you attempt this.

My gum getting thrown out the window of the car going down the highway appears to stay along side me. Now, someone get a car, a ball, and a high speed camera and test this out for us.

If you reduce the profile, and therefore the area that wind resistance acts upon, the effect is seen less.

Alternatively, instead of a ball or gum use a sheet of paper. Switch the gum with a new, flat sheet of paper.

You guys are in some sense both right, when you toss the ball out of the car it will be moving at the speed of the car for a tiny fraction of time until wind resistance acts on it. The key though is that the ball is not going to stay in the air very long. The ball is going to accelerate downwards at 9.8m/s^2. It does not matter the velocity of the object, just as a bullet fired from the same height as a ball is dropped will hit the ground at roughly the same time.

Spacey wrote:Not true, unless you are saying there is not resistance due to wind.

When you are driving down the highway at 100, or a street at 60 ask your passenger to throw a tennis ball directly ball into the air... see what happens. Make sure there is no one behind you before you attempt this.

The underlined part should have said "throw a tennis ball directly up".

Come_Forth wrote:You guys are in some sense both right, when you toss the ball out of the car it will be moving at the speed of the car for a tiny fraction of time until wind resistance acts on it. The key though is that the ball is not going to stay in the air very long. The ball is going to accelerate downwards at 9.8m/s^2. It does not matter the velocity of the object, just as a bullet fired from the same height as a ball is dropped will hit the ground at roughly the same time.

I would argue that as soon as the arm/hand is out the window wind resistance is acting on the ball, because you are not stationary. Air is moving over the car as you drive in it. I would further say that the fraction of time that wind resistance is not acting on the ball is negligible because you can feel air acting on your hand as it goes out the window and thus on the ball partially exposed in your hand.

If you were to toss a ball out of the car the resistance due to air effect is still acting on the ball, in the opposite direction of the mass' momentum, as the ball passes through air and bumps molecules in the air. Once it gets out the window the air is moving in another direction. If you look at it in a high speed camera (aerial view) it will look like the ball is curving as it travels back.

I get what you are saying spacey. The point about the ball only being in the air for a fraction of a second was to show that the ball will not "travel" with the car. Even if you hold your hand outside the window with the ball it will still be traveling at 60. I am not sure how to calculate the wind resistance at that speed because I would need the mass of the ball and the surface area and the temperature, I believe that it should curve forward until it hits the ground if it is a metal ball. If it is a tennis ball as you were saying earlier it will curve backwards. This is shown on this site http://www.physics.upenn.edu/courses/gladney/mathphys/java/sect4/subsection4_1_2.html

but if that car travelled in vacum phlam and spacey can drop their balls and they'll land next to the car.

Corran Horn wrote:but if that car travelled in vacum phlam and spacey can drop their balls and they'll land next to the car.

Lol, I was just about say that. It doesn't matter cause there is no wind in space

depends. there is solar wind, but the ball is to small to be afected by it anywaus..

ah.. btw:

You found him!

Corran Horn wrote:depends. there is solar wind, but the ball is to small to be afected by it anywaus..

then tell Thaltek to stop screaming!