SpudFiles

Sorry about the quality of the video, I'm horrible at making them! Anyway all you have to do is fire your cannon straight into the air, count the time it takes to hit the ground again, divide that in half, and multiply it by the acceleration due to gravity (either 9.8m/s/s or 32ft/s/s) and you get the velocity of the object you fired

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And as a corollary to what Jack said, if you have got a projectile that's coming back down at a similar speed to that at which it went up, firing it straight up into the air is rather dangerous...

ummm I have 2 questions as it's been decades since I took physics...

1: how does this figure air resistance?

2: how do I get the projectile to come straight-ish down? I rarely get that to happen with a paintball gun (lying on my back with goggles on, grinning) despite many attempts

POLAND_SPUD wrote:chrono connect mobile

How does that work, time between shot sound and impact sound?

I rarely get that to happen with a paintball gun (lying on my back with goggles on, grinning) despite many attempts

I am proud and honored to live on the same land mass as you sir

How does that work, time between shot sound and impact sound?

Exactly. Add to that some ballistic calculator and you've got a nice tool for airgunning

Welcome to the board ~NooooooB~ (hey, you picked the name )

1. Air drag is pretty significant.
2. The projectile doesn't hit the ground with the same velocity as the muzzle velocity, it hits moving at some fraction of the object's terminal velocity. (For a tennis ball the terminal velocity is about 100 FPS which is a lot lower than the muzzle velocity of even a basic spud gun.)

See here.

If you don't have a true shooting chrony either build one or just use a laptop (or smart phone) to record the sound of firing against a hard target at fairly short range. A sound analysis program (like Audacity) can extract the flight time between the two bangs. A tape measure and a paper and pencil is all that is needed to calculate the average velocity over the firing distance. If you tilt the target you can keep the round from bouncing back and hitting you in the head.

I can see that I've made a bit of a failure now

We always kick noobies in the butt once, just so they don't get too big a head.
We also randomly kick experienced spudders just to be a-holes. :bounce:

jimmy101 wrote:We also randomly kick experienced spudders just to be a-holes. :bounce: