Post by ding on Dec 4, 2008 20:31:07 GMT 10
This is cool! Here is an energy calculator
www.1728.com/energy.htm
I plugged in 450grams at 80k which is I think about worst case for my foamy. That gives an energy of 111 joules.
A heavy foamy (900g) doing 120k (possible at SC) has 500 joules. A 2kg mouldie doing 140 has 1500 joules of energy. It's amazing how weight and speed mount up the energy.
A tennis ball weighs 56g. According to the Guinness book of records the fastest recorded serve is 163 MPH or 260 kmh Assuming a realistic serve speed of 150k the energy is about 50 joules. A cricket ball weighs 160 grams. The fastest bowl is 160k to date. Assuming someone could bowl at 120 thats about 90 joules of energy. Pretty interesting stuff.
I copied this table from the wiki on muzzle enrgy.
en.wikipedia.org/wiki/Muzzle_energy/url]
Firearm Caliber Muzzle energy (ft • lbf) (J)
air gun .177 5 7
rifle .22LR 100 135
rifle 5.56x45 mm 1200 1550
pistol (semi-auto) 9 mm 350 540
Clearly being foam they don't hit as hard as any of the above examples because they absorb energy. Also because they are so big the most likely outcome is that you would have a glancing blow. I'm pretty confident that I about my assertion that I'd rather be hit by a foamy than a tennis ball is still right.
I'll let you all calculate the energy of your models. What scares me is my F3A history. I flew aeroplanes that weighted 5kg and cruised at 160k (diving speed would be much higher). That's 4938 Joules... or 3.5 times being hit by a rifle.... I'm really not sure which I'd rather... shot with a rifle or a direct hit by an f3a model at cruise speed....
Anyway, food for thought.
www.1728.com/energy.htm
I plugged in 450grams at 80k which is I think about worst case for my foamy. That gives an energy of 111 joules.
A heavy foamy (900g) doing 120k (possible at SC) has 500 joules. A 2kg mouldie doing 140 has 1500 joules of energy. It's amazing how weight and speed mount up the energy.
A tennis ball weighs 56g. According to the Guinness book of records the fastest recorded serve is 163 MPH or 260 kmh Assuming a realistic serve speed of 150k the energy is about 50 joules. A cricket ball weighs 160 grams. The fastest bowl is 160k to date. Assuming someone could bowl at 120 thats about 90 joules of energy. Pretty interesting stuff.
I copied this table from the wiki on muzzle enrgy.
en.wikipedia.org/wiki/Muzzle_energy/url]
Firearm Caliber Muzzle energy (ft • lbf) (J)
air gun .177 5 7
rifle .22LR 100 135
rifle 5.56x45 mm 1200 1550
pistol (semi-auto) 9 mm 350 540
Clearly being foam they don't hit as hard as any of the above examples because they absorb energy. Also because they are so big the most likely outcome is that you would have a glancing blow. I'm pretty confident that I about my assertion that I'd rather be hit by a foamy than a tennis ball is still right.
I'll let you all calculate the energy of your models. What scares me is my F3A history. I flew aeroplanes that weighted 5kg and cruised at 160k (diving speed would be much higher). That's 4938 Joules... or 3.5 times being hit by a rifle.... I'm really not sure which I'd rather... shot with a rifle or a direct hit by an f3a model at cruise speed....
Anyway, food for thought.