Air Compressors WA. Supplying you with Information on Air Compressor Technology.
Industrial Air Compressors | What You Need to Know
What You Need To Know About Air Compressors!
Need to know more about Air Compressors. Are you researching what to buy to fit what you need or just simply learning about whats new, Air Compressor WA has the information.
A question about the muzzle energy of a pumpkin…?
Took the family to the local "Oktoberfest" today for the hay rides and other activities, and they had a "Punkin Chunker" there. For $3.00 you can pull the trigger on the punkin chunker and try to hit a beat up pick up truck about 100 yards downrange. Really is a lot of fun. It’s basiscally a huge air gun attached to an industrial air compressor that shoot the pumpkin out of a 15 ft. long or so barrel.
Anyhow, I got to thinkin, this looks like it is quite powerful and started thinking about the ballistics. It seems to take about 1.5 seconds to hurl a pumpkin what looks to be just about 100 yards with about 30 vertical feet of arc in the flight path. I’m guessing that each pumpkin is in the nieghborhood of 5 lbs. and the muzzle velocity somewhere around 300 fps.
This comes out to a muzzle energy of nearly 7000 foot pounds with each pumpkin, does this sound right? 7000 foot pounds is so much more powerful than all but the most magnum rifles, yet this guy is out here chucking pumpkins with that much force, I must be mistaken. How much kinetic energy do you think a pumpkin has in this scenario?
I don’t have the formula for figuring the kinetic energy of a pumpkin whose weight is figured in pounds rather than in grains. However, you can convert pounds to grains by multiplying by 7,000. nce you have the weight in grains, you can calculate the foot pounds of kinetic energy by multiplying the weight of the pumpkin in grains times the square of the velocity in ft./sec. and dividing by 450,400. If we assume that your figures are correct, a 5 pound pumpkin will weigh 35,000 grains. If that mass is moving at a velocity of 300 fps, we can multiply 35,000 by 300 squared and divide by 450,400. Doing this we get 6993.7 ft.pounds of kinetic energy. This confirms you calculation of "nearly 7,000 ft. pounds". The reason for this amount of kinetic energy is the tremendous mass of the pumpkin as compared to the mass of a bullet.
4 Responses to “A question about the muzzle energy of a pumpkin…?”
Leave a Reply
Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisis at vero eros et accumsan et iusto odio dignissim qui blandit praesent luptatum zzril delenit augue duis dolore te feugait nulla facilisi.
Dude stay away from math it will make you sad in the long run.
References :
I don’t have the formula for figuring the kinetic energy of a pumpkin whose weight is figured in pounds rather than in grains. However, you can convert pounds to grains by multiplying by 7,000. nce you have the weight in grains, you can calculate the foot pounds of kinetic energy by multiplying the weight of the pumpkin in grains times the square of the velocity in ft./sec. and dividing by 450,400. If we assume that your figures are correct, a 5 pound pumpkin will weigh 35,000 grains. If that mass is moving at a velocity of 300 fps, we can multiply 35,000 by 300 squared and divide by 450,400. Doing this we get 6993.7 ft.pounds of kinetic energy. This confirms you calculation of "nearly 7,000 ft. pounds". The reason for this amount of kinetic energy is the tremendous mass of the pumpkin as compared to the mass of a bullet.
References :
I have seen these and I can tell you your time estimate seems VERY low to me. Try calculating with 100 feet per second, and even that is just a 3 second flight for a 100 yard target.
Of course, this is why people need to measure things with rulers and stopwatches and scales
References :
Try 200 FPS, … (300′/1.5Sec.).
You’re right. It still works out to one big number!
I think you’re under-estimating the time, and overestimating
the ‘punkin’ though. There’s a lot of air in them.
References :