Are These People Christians

[Hogg]

I say closer to 80mph, maybe less, a marble does not weigh one oz, a penny weighs about a gram, pick up 28 pennies, much heavier than a marble. Terminal Velocity of a penny is about 55mph or (thick) 84 fps.

thick, 130mph is roughly 191 fps

I guess we have to establish the definition of a marble. there are two, maybe three, maybe four different sizes and flavors of marbles. The kind that kids play marbles with are roughly 3/4" in diameter, clear glass (usually), and have a decorative glass pattern inside. However, I also recall smaller marbles that typically came in colors and were about 1/2" in diameter best case....and not even totally spherical. And I recall another type of marble that was somewhere between the two, clear glass with the center pattern, and probably somewhere in between in terms of diameter......but with your illustration of a penny, I'd wager that even the largest size that I can think of would weigh no more than 16 pennies. I would expect that the specific gravity of glass is greater than copper but I do not have a materials handbook within reach right now.

Given the foregoing, what is the terminal velocity of a marble?

We need the following variables:

Cd = drag coefficient
rho = fluid density
A = area
m = mass

if you have the density on hand and the drag coefficient, we're halfway there. As far as area, we could go and snag a bag of marbles from a kid. But since we do not know these numbers, lets compare some known values for various objects:

Terminal velocities for various objects:

baseball = 141 ft/s
Golf ball = 144 ft/s
hail stone = 46 ft/s
rain drop = 30 ft/s
165# person = 197 ft/s

Now, the only object that will hit a 130mph or roughly thereabouts is a person so my number on the marble is definitely off. A marble is heavier than a hailstone, lighter than a golf ball, but of less surface area and has a heavier mass per unit volume......but its still not going to get close to 190 ft/s. Your guess, roughly 117 ft/s is probably about right for a small marble and probably a little light for the larger one. Ultimately, what is the mass of a 3/4" diameter sphere of glass? We can work the rest backwards from there.

Now I'd suspect that the pachinko ball can get going pretty good....perhaps someone wants to crunch out the numbers.

 

[thick]

lmao i carried an extra zero. I was writing on a small sticky pad. I knew it couldnt add up and shouldve recalculated but u got the point i was trying to make

thick, 130mph is roughly 191 fps

I guess we have to establish the definition of a marble. there are two, maybe three, maybe four different sizes and flavors of marbles. The kind that kids play marbles with are roughly 3/4" in diameter, clear glass (usually), and have a decorative glass pattern inside. However, I also recall smaller marbles that typically came in colors and were about 1/2" in diameter best case....and not even totally spherical. And I recall another type of marble that was somewhere between the two, clear glass with the center pattern, and probably somewhere in between in terms of diameter......but with your illustration of a penny, I'd wager that even the largest size that I can think of would weigh no more than 16 pennies. I would expect that the specific gravity of glass is greater than copper but I do not have a materials handbook within reach right now.

Given the foregoing, what is the terminal velocity of a marble?

We need the following variables:

Cd = drag coefficient
rho = fluid density
A = area
m = mass

if you have the density on hand and the drag coefficient, we're halfway there. As far as area, we could go and snag a bag of marbles from a kid. But since we do not know these numbers, lets compare some known values for various objects:

Terminal velocities for various objects:

baseball = 141 ft/s
Golf ball = 144 ft/s
hail stone = 46 ft/s
rain drop = 30 ft/s
165# person = 197 ft/s

Now, the only object that will hit a 130mph or roughly thereabouts is a person so my number on the marble is definitely off. A marble is heavier than a hailstone, lighter than a golf ball, but of less surface area and has a heavier mass per unit volume......but its still not going to get close to 190 ft/s. Your guess, roughly 117 ft/s is probably about right for a small marble and probably a little light for the larger one. Ultimately, what is the mass of a 3/4" diameter sphere of glass? We can work the rest backwards from there.

Now I'd suspect that the pachinko ball can get going pretty good....perhaps someone wants to crunch out the numbers.

 

[Bob Smith]

In the past month or two, Mythbusters did a similar expiriment testing the idea that a penny thrown off the Empire State Building would slice through the roof of a car or become embedded inside the sidewalk if it didnt hit a car. The results...it wouldnt come close to cutting through a metal roof of a car. It would slightly chip the sidewalk but certainly wouldnt become embedded. And in the end, it wouldnt kill a person either. It would cause a serious bruise if it hit skin and a real nice headache if it hit your head.

Heres your marble size and weight chart. By govt standards, I think marbles are obese.

http://www.landofmarbles.com/marbles-measuring.html

 

[Bob Smith]

Stinkin link. It said "size and weights" and then didnt actually give weights!

 

[Hogg]

lmao i carried an extra zero. I was writing on a small sticky pad. I knew it couldnt add up and shouldve recalculated but u got the point i was trying to make

I always get your point thick, but in a manner different than Mr. Smith.....i do not wake up in the morning with a sore culo

 

[Bob Smith]

I always get your point thick, but in a manner different than Mr. Smith.....i do not wake up in the morning with a sore culo

Why the hell have I been the target lately?? This sucks!

 

[Mark Kerr]

Well, I was a golfer in high-school (SHUT UP!) and I was hit TWICE in the head with golf balls. I was hit in the back of the head by a golf-ball coming off of a driver. I was hit maybe 30 yards from the teebox, so that means the mass of a golfball was traveling well over 100 mph and it didnt break the skin. Knocked for a loop (it hit me right behind the ear BTW) and I couldnt stand for a while, but it didnt go through my head.

[MK]

P.S. I know you werent saying a marble could slice through someone literally, but I was making the case that it would do far less damage than most people predict.

 

[Hogg]

Why the hell have I been the target lately?? This sucks!

Oh right, you know you love it. How are your eyelids this morning

 

[dolfe1]

Well, I was a golfer in high-school (SHUT UP!) and I was hit TWICE in the head with golf balls. I was hit in the back of the head by a golf-ball coming off of a driver. I was hit maybe 30 yards from the teebox, so that means the mass of a golfball was traveling well over 100 mph and it didnt break the skin. Knocked for a loop (it hit me right behind the ear BTW) and I couldnt stand for a while, but it didnt go through my head.

[MK]

P.S. I know you werent saying a marble could slice through someone literally, but I was making the case that it would do far less damage than most people predict.

This explains a lot.

 

[Hogg]

Well, I was a golfer in high-school (SHUT UP!) and I was hit TWICE in the head with golf balls. I was hit in the back of the head by a golf-ball coming off of a driver. I was hit maybe 30 yards from the teebox, so that means the mass of a golfball was traveling well over 100 mph and it didnt break the skin. Knocked for a loop (it hit me right behind the ear BTW) and I couldnt stand for a while, but it didnt go through my head.

[MK]

P.S. I know you werent saying a marble could slice through someone literally, but I was making the case that it would do far less damage than most people predict.

Hmmm, law school, mensa, a golfer.....let me guess, you are also of anglo-saxon descent, protestant, and have a pure bloodline?

Just kidding, you're actually a very bright fellow MK....dont know if I have ever told you that.

That golf ball must have hurt like heck.

 

[Bob Smith]

That golf ball must have hurt like heck.

It doesnt hurt so much here....or here...