Stumped on physics problem (1 Viewer)

SWJJ

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In an historical movie, two knights on horseback start from rest 70.9 m apart and ride directly toward each other to do battle. Sir George's acceleration has a magnitude of 0.201 m/s2, while Sir Alfred's has a magnitude of 0.287 m/s2. Relative to Sir George's starting point, where do the knights collide?


Using the Kinematic Equations of motion where do these fokkers meet?

After starring at the problem for an 20 min, and drinking 2 vodka frescas whilst sracthing my head I cannot figure this one out...

georgie's a is positive, Alfreds negative relative to Georgie they will meet at point x, relative to alfred its 70.9 - x...

initial velocity will be 0 for both, but I do not know time or final velocity for either...

Suggestions?
 

austinwes

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Distance Traveled is 1/2 acceleration times time squared. They reach each other when the sum of both distances traveled equals 70.9. So, you find the time by 1/2*a1*t^2+1/2*a2*t^2=70.9. Then once you do that you sub that time back into 1/2*a*t^2 for sir george.
 

SaintAkira

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Did I just have a seizure?

Must be the vodka.

BTW, good luck with that problem.
 

Joe OKC

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WOW....

Here, lets try a real problem.

Two strippers are fighting in the dressing room. Which one is wrong?

Joe
 

Jared1979

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Distance Traveled is 1/2 acceleration times time squared. They reach each other when the sum of both distances traveled equals 70.9. So, you find the time by 1/2*a1*t^2+1/2*a2*t^2=70.9. Then once you do that you sub that time back into 1/2*a*t^2 for sir george.

I found a more general equation with taking the difference to equal 70.9 (Knight 2 has negative aceleration).

How I derived it:
X = Xo + Vo t + .5 a t^2

X1 = .5 a1 t^2

X2 = 70.9 + .5 a2 t^2

Let X1 = X2

.5 a1 t^2 = 70.9 +.5 a2 t^2

.5 a1 t^2 - .5 a2 t^2 = 70.9
-------------------------------

.5 a1 t^2 + .5 a2 t^2 = 70.9 will work if you ignore the negative acceleration, but that will pose a problem if the two objects are travelling in the same direction.

----------------------------------
100% agree with the rest though
 

StChadwick

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WOW....

Here, lets try a real problem.

Two strippers are fighting in the dressing room. Which one is wrong?
The answer is you can take the man out of the strip club but you cant take the strip club out of the man :9:
 

Doobsdemons

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They meet in a pub and discuss why they have to fight for a king they didn't vote for. After a few pints of Harp, they realize they don't vote for kings. Sir Alfred being the quicker of the two unsheaths his sword and aims to do in Sir George. However, Sir Alfred is quite drunk at this point, misses his mark and slays the barkeep. Horrified, both good knights flee the pub only to be confronted by a regiment of King Edward's best men. Both, though still very drunk, managed to fight through the mob and escape. Nothing was heard from them for several years. It was rumored they had escaped to France or Saxony (what is now present day Germany). In 1928 a sword was found in Virginia with an insrciption on the blade. It was simply the letter A. Did it belong to Sir Alfred? Carbon dating puts the age of the sword at about the time he lived, but at this point one can only speculate. Hope this helps your physics problem.
 

Doobsdemons

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What's to discuss?

"The lady of the lake, her arm clad in the purest shimmering samite, held aloft Excalibur from the bosom of the water ..."

Listen, strange women lyin' in ponds distributin' swords is no basis for a system of government. Supreme executive power derives from a mandate from the masses, not from some farcical aquatic ceremony.
 

tenordas

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Listen, if I went 'round sayin' I was an Emperor just because some moistened bint had lobbed a scimitar at me, they'd put me away!

but what's the equation to figure exactly where in the arc of the throw I caught that scimitar?... :mwink:
 

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