Calculating Projectile Force from Rotational Velocity of a Throwing Sling

[Riley Werling]

Hey, I am not sure if this should be posted somewhere else, if so if you could direct me it would be much appreciated. So my question is how would i find the rotational velocity of a sling and how i could use that to calculate the force of a projectile from said sling. I've tried doing some research online but most of what I've read is way over my head so i was hoping someone here might be able to help me.

Thanks for any and all help you guys provide.

 

[Nidum]

I assume that you are talking about a real sling - that is two thongs and a pouch which are whirled around until one of the thongs is released and the projectile flies free ?

The whirling speed is really determined by choice by the person using the sling . The speed picked up by the projectile is a simple function of the whirling speed and the effective length of the sling .

The effective length of the sling is the length of the thongs plus some additional length from your arms .

So how fast (rpm) can you whirl a sling and what is the effective length of your sling ?

 

[Nidum]

Hint : For simplicity you can assume that the centre of rotation for the whirling is at you shoulder . Remember that your arms will most likely be bent .

 

[Riley Werling]

So how fast (rpm) can you whirl a sling and what is the effective length of your sling ?[/QUOTE]
Sling would be 48in long and idek what rpm would be.. can't find an average anywhere online socichave no clue

 

[Nidum]

How fast can you whirl your arms around ?

 

[Riley Werling]

Pretty fast, if youre asking for a number i couldn't tell you

 

[Nidum]

Whirl you arm as fast as possible and count the number of rotations made in a minute or if you can't manage a complete minute try thirty seconds .

 

[Riley Werling]

Whirl you arm as fast as possible and count the number of rotations made in a minute or if you can't manage a complete minute try thirty seconds .

100

 

[Nidum]

So 100 turns in 1 minute or 100 rpm . Good .

100/minute is 100/60 = 1.67 revs/second .

The speed of the sling pouch as it goes around in a circle is given by 2 * pi * L * (revs/second) where L is the effective length of the sling .

L= 48 inches but we'll convert that to metres for our calculations . So we'll use L = 1.2 metres .

Do you want to try working out the pouch speed ?