Slinging.org Forum - Re: Speed of projectiles

Stein Vegard Descens Offline The n00b... Posts: 158 In the south of sweet, Norway Gender:	Re: Speed of projectiles Reply #15 - Nov 2^nd, 2005 at 10:40am Thanks Gard... I seriously had a problem to answer that...
Back to top	Read your Bible.... IP Logged

Yurek

Funditor
Past Moderator

Offline

The best thing, is a good
sling.

Posts: 942
Poland
Gender: male

Re: Speed of projectiles
Reply #16 - Nov 2^nd, 2005 at 1:55pm

Quote:

Tint, I believed I'd heard somewhere that the distance was 20 metres, so if that's wrong...
The stone uses 0,57 second from release to when it hits the white thing.
20 meters divided on 0,57= 35,0877193 mph =126,315789 km/t
But, as I said, I'm not sure the distance is right.

Gard

Gard I'm curious how you got that time. Could you explain your way?

The mentioned calculations are here:

http://www.slinging.org/forum2/yabb/YaBB.cgi?board=1;action=display;num=11242891...

I estimated the time at the 0.4 s (1/15 * 6 frames), what gives:

20m/0.4s = 50 m/s = 180 km/h = 111.8/h

of the averange velocity, not the muzzle velocity.

Jurek

Back to top

In the shape, structure and position of each stone, there is recorded a small piece of history. So, slinging them, we add a bit of our history to them.

IP Logged

Gard

Senior Member

Offline

Yup, there are slingers
in Norway too!

Posts: 396
Norway
Gender: male

Re: Speed of projectiles
Reply #17 - Nov 2^nd, 2005 at 4:26pm

I did like you, but I got the time 0,57 seconds.
20 m / 0,57 = 35,0877193 meters/second = 126,315789 kilometers/hour
I don't know how I could done it different, when I got the time 0,57 second.
But, if you got the time 0,40, it'll be 20 / 0,40= 50 meter /second = 180 km/h.
I'm not sure who's time is right, but I got the time 0,57 seconds Undecided

A friend of me got 0,6 seconds when he measured.

Gard Embarrassed

Back to top

You never know what you might get to need, before you need it.

IP Logged

Tint Interfector Viris Spurii Past Moderator Offline Posts: 2348 Hong Kong Gender:	Re: Speed of projectiles Reply #18 - Nov 2^nd, 2005 at 8:42pm I thought movies were at least 24 frames per second ??? Was it just 15 frames/sec?
Back to top	IP Logged

Yahweh Bless you in Yeshua Interfector Viris Spurii Offline Matthew 11:25-30 Posts: 1700 Gender:	Re: Speed of projectiles Reply #19 - Nov 2^nd, 2005 at 9:01pm I will be using a camera at 30fps this weekend.....and we will have a definitive speed averaged from flight time. Of course it certainly won't be pretty watching me try to replicate the days of yore.... At least I'll have a visual record for the insurance agent. TS
Back to top	Blessings in Yeshua!&& IP Logged

lobohunter Interfector Viris Spurii Offline where be a rock and a string there be a sling Posts: 1985 Cottage Grove or Gender:	Re: Speed of projectiles Reply #20 - Nov 2^nd, 2005 at 9:03pm seems to me every body needs a freind and a stop watch i think if we could get several sets of results from several people at a set distance say 20m we could come up with a true range or average possibley a standard ammo such as a 3ounce lead egg sinker or a golf ball
Back to top	IP Logged

Tint Interfector Viris Spurii Past Moderator Offline Posts: 2348 Hong Kong Gender:	Re: Speed of projectiles Reply #21 - Nov 2^nd, 2005 at 9:08pm I am in! 8)
Back to top	IP Logged

Tumakas Descens Offline I'm slinging in the rain! Posts: 173 Las Vegas, NV Gender:	Re: Speed of projectiles Reply #22 - Nov 2^nd, 2005 at 10:22pm Same here! Just list the projectile type, weight and distance and i'll see if i can get a vid that has me getting somewhere near the target.
Back to top	IP Logged

Yurek

Funditor
Past Moderator

Offline

The best thing, is a good
sling.

Posts: 942
Poland
Gender: male

Re: Speed of projectiles
Reply #23 - Nov 3^rd, 2005 at 12:12pm

Quote:

I did like you, but I got the time 0,57 seconds.
20 m / 0,57 = 35,0877193 meters/second = 126,315789 kilometers/hour
I don't know how I could done it different, when I got the time 0,57 second.
But, if you got the time 0,40, it'll be 20 / 0,40= 50 meter /second = 180 km/h.
I'm not sure who's time is right, but I got the time 0,57 seconds Undecided

A friend of me got 0,6 seconds when he measured.

Gard Embarrassed

Gard,

I know you got the 0.57 from your previous post

But, my question was: how did you get that time? What way of measure did you use? I was just curious. Doesn't matter if I got the 120 or 180 km/h, either if my estimation is exact or not. Could you exactly explain your measure? Anyway, I'm glad you like me

Tint,

I used a Canon's digital camera for still images, it gives only the 15 frames per sec. It is not a typical camcoder, so movies made by it are not the best. You can see, that the frame period is somewhat inregular, the 15 frms/s is an averange rate.

lobohunter

That is a good idea, but I think a stop watch is very unacurate tool at the 20 m. The time is too short, no body is able to cath a reliable measure.

Anyway, I'm also in 8)

Jurek

Back to top

In the shape, structure and position of each stone, there is recorded a small piece of history. So, slinging them, we add a bit of our history to them.

IP Logged

Gard Senior Member Offline Yup, there are slingers in Norway too! Posts: 396 Norway Gender:	Re: Speed of projectiles Reply #24 - Nov 3^rd, 2005 at 12:27pm First I measured how much time the whole video used, and then I divided it on how many pictures there is, so that I knew how long time one picture was. Then I counted how many pictures there was from release to when it hits, x how long time one picture was. Gard
Back to top	You never know what you might get to need, before you need it. IP Logged

lobohunter Interfector Viris Spurii Offline where be a rock and a string there be a sling Posts: 1985 Cottage Grove or Gender:	Re: Speed of projectiles Reply #25 - Nov 6^th, 2005 at 10:01pm you maybe right yurek sop watchs are common. my be the distance should be increased I think a hundred yards is to far. worried about deceleration. not sure if fifty meters would be much differnt than 20 meters. What Does everybody say to golf balls at 75 meters at some thing large such as a barn
Back to top	IP Logged

Tint Interfector Viris Spurii Past Moderator Offline Posts: 2348 Hong Kong Gender:	Re: Speed of projectiles Reply #26 - Nov 6^th, 2005 at 10:06pm Is it necessary that we put a restriction on the distance? Couldn't everyone just use whatever range they want, as long as they can explain how the speed was calculated? I am thinking of using a radar speed gun!
Back to top	IP Logged

Tumakas Descens Offline I'm slinging in the rain! Posts: 173 Las Vegas, NV Gender:	Re: Speed of projectiles Reply #27 - Nov 7^th, 2005 at 1:23am Being a wannabe scientist and to up hold what I learn in Chemistry I think that we must have the same projectile, weight, and distance as a control then we can throw in other things to experiment. So do we have any agreed on variables like what brand or type of golf ball to use?
Back to top	IP Logged

lobohunter Interfector Viris Spurii Offline where be a rock and a string there be a sling Posts: 1985 Cottage Grove or Gender:	Re: Speed of projectiles Reply #28 - Nov 7^th, 2005 at 6:17am Tumakas; ty those are my points excactly
Back to top	IP Logged

Gard Senior Member Offline Yup, there are slingers in Norway too! Posts: 396 Norway Gender:	Re: Speed of projectiles Reply #29 - Nov 7^th, 2005 at 9:35am What about putting up a net, and have the camera behind it, and shoot at the net while the camera records? It would make it easy to see release, and when the stone hits. Just be careful with using small stones... Gard
Back to top	You never know what you might get to need, before you need it. IP Logged