Author Topic: Math problem for you.. (Read 1892 times)

ABaker · « **on:** June 21, 2004, 05:31:06 PM »

If my 22-250 shoots a 45 grain bullet at 4000 feet per second, how many miles per hour does that convert too? Any takers?

KN · « **Reply #1 on:** June 21, 2004, 06:18:05 PM »

2727.272727272727272727mph. I think I did that right. KN

DirtyHarry · « **Reply #2 on:** June 21, 2004, 06:55:48 PM »

KN, You Did...

Magnanova1 · « **Reply #3 on:** July 03, 2004, 06:33:20 PM »

for an airplane, thats mach 3.8

DannoBoone · « **Reply #4 on:** July 04, 2004, 06:14:23 AM »

Quote from: Magnanova1

for an airplane, thats mach 3.8

......and for a prairie dog, that's total separation of all body parts.. :-D

bigjeepman · « **Reply #5 on:** July 04, 2004, 08:10:26 AM »

The formula is ... fps x 0.6818 = mph

goose7856 · « **Reply #6 on:** September 23, 2004, 04:58:56 PM »

hey im in chem honors this year as a sophomore, and i was tryin to use somethin called dimensional analysis, or otherwise called.......CONVERTING UNITS :grin:

I am jw where the .68.... came from??

haha lol i just worked it a different way (the way we learned in class), and got it right!!

wierd how probs can be worked so many different ways!! i worked it totally diff.!!

This is my setup:

4,000 fps/ 3,600 sec/ 1 mile = 14400000
1 sec / 1 hour / 5,280 feet = 5280

that equals 2727.2727272727.....

wow thats weird how school can actually help in real life.....jus wanted to see if it worked.....sry to bore yall with the science lesson HAHA (O by the way, if you dont understand what i was doing, is i crossed canceled the units for ex: 4,000 feet/1 mile
/ 5,280 feet

just cancel the units but im sure all of yall kno how to do that!! :grin:

again, sry for the lecture!!

Judson · « **Reply #7 on:** January 04, 2005, 11:53:11 AM »

That is rather easy. 4000 divided by 88 times 60 this will give you 2727 MPH. Now you tell me what the 88 is all about

alsatian · « **Reply #8 on:** January 05, 2005, 04:38:46 AM »

goose7856:

You did it the only way there is to do it. The only difference between your approach and the other is you showed all your work. By the way, the factor 0.6818 is what remains if you remove the bullet velocity -- 4000 fps -- from your expression and then you reduce your expression (I suppose there should be a units factor of (MPH/fps) in the conversion factor). Doing so leaves a conversion factor, the 0.6818 value, which can be multiplied by any fps velocity to convert to mph.

Work hard in school and take challenging courses and it will pay off in life.

goose7856 · « **Reply #9 on:** January 05, 2005, 11:11:38 AM »

thanx, and I will keep studying hard......only a sophomore right now, but ive already got alot of my plans for college planned out......

I think I either want to go to #1 Duke, #2/#3 Wake Forest/Virginia (I need to look into those schools a little more :lol: but they are right behind Duke.)

Then I want to go to pre-med school, and graduate.....and come back home to louisiana and get a graduate degree at LSU....then do all the training, etc until I can become a certified anestisiologist (?) (I have NO CLUE how to spell it, but the person that puts people to sleep for surgory, etc)

Ive really been trying to wrok hard, and the honors courses let my 4.0 GPS drop to a 3.9, but I only missed an A by 1/2 a point, so maybe I can pull it up to all A's this semester??!!

Thanx for the advice, and hopefully my plans can some true some day??!!!!!!

Judson · « **Reply #10 on:** January 05, 2005, 03:44:39 PM »

Hay Alsation, I got it right also and no one has yet told me what the 88 or the 60 is all about!!!! It is really simple and it is easier unless you want to figure in drag, and some other stuff like time of flight and such. Math can be fun but not as they teach in school!

goose7856 · « **Reply #11 on:** January 05, 2005, 03:50:24 PM »

Quote

Math can be fun but not as they teach in school!

You could not be more right!! :-D :-D

alsatian · « **Reply #12 on:** January 06, 2005, 06:02:31 AM »

Quote from: Judson

Hay Alsation, I got it right also and no one has yet told me what the 88 or the 60 is all about!!!! It is really simple and it is easier unless you want to figure in drag, and some other stuff like time of flight and such. Math can be fun but not as they teach in school!

Judson:

Your (60/88) factor includes multiplying through by 60 to correct for either minutes or seconds and dividing by 88 to correct for feet and either seconds or minutes. Specifically,

4000 fps = (4000 fps)(1 mile/5280 feet)(60 seconds/minute)(60 minutes/hour)

4000 fps = (4000 fps)(mile seconds/88 feet*minute)(60 minutes/hour)

4000 fps = 4000 (f/s)(mile*seconds)(1/hour*feet)(60/88)

4000 fps = 4000 (60/88)(mile/hour)

The units get cancelled out, as for example feet/feet = 1.

So, 60/88 is just the way somebody decided to reduce the math. This fraction is equal, by the way, 0.6818 as above. You just complete the division of 60 by 88.

ShadowMover · « **Reply #13 on:** January 06, 2005, 07:58:49 AM »

I sure hope the future anesthesiologist gets his spelling and math right before he gets out of school. I can't think of a quicker way to kill someone than to give them the wrong anesthetic or the wrong amount. These are really high school level skills, or they were.

goose7856 · « **Reply #14 on:** January 06, 2005, 10:32:26 AM »

what!! I got the math prob. right........

and the only word I couldnt spell was aneste....w/e.....yea so I dont think thats very important....im taking Chemistry right now though and the Element and Polyatomic ion names are pretty important to make sure the person wakes up!!. :eek: :lol:

victorcharlie · « **Reply #15 on:** January 06, 2005, 12:29:14 PM »

Don't worry Goose........I'd rather have someone that know how much gas to give me than someone that knows how to spell the name of the gas but guesses at the quantity.

The way I figure it, you got to do 40+ hours a week some where. You might as well make the big bucks doing what you want to do.......

I say Go for it!

Judson · « **Reply #16 on:** January 06, 2005, 12:29:50 PM »

Not bad!!! 60 miles per hour equals 88 feet per second.