Physics Help!!

zzinco79 · 10-03-2007, 10:36 PM

No time to explain!! It is due by midnight!!!

I tried them but it wasn't worked out

Please help!!

canucklion · 10-03-2007, 10:50 PM

when in doubt, E= MC^2

that's how I (barely) passed physics 101

zzinco79 · 10-03-2007, 10:53 PM

haha

Yea.. I (barely) passed my physics 311 with F = ma.

TurboFan · 10-03-2007, 10:59 PM

1. Start with a free body diagram, and it will start to work itself out. The sum of the forces must equal the mass multiplied by the acceleration. You can find acceleration with your motion equations - v(final)=v(initial) + .5*a*t^2. I think I remember that correctly...v(final) = 5m/s, v(initial)=-4m/s, t= 3 seconds. Solve for a.

Now setup the equation: f2*cos(theta)-f1 = m * a. Solve for theta.

2. F=m*A. m = 12,0kg, A= 9.81m/s^2. If nothing is moving, the force on the box from the floor must counter gravity exactly, so the force exerted on the box is 117.72N (newtons).

You've made my brain hurt tonight, and confirmed what I feared most - I've not consumed enough alcohol to counter the effects of college. My engineering mechanics are a little rusty, I may have just given you the dimensions for the playmate of the month.

I'm off to get a beer!

aequitas330 · 10-03-2007, 11:05 PM

Reminds me of this....

canucklion · 10-03-2007, 11:05 PM

^ I concur

zzinco79 · 10-03-2007, 11:10 PM

Quote:

Originally Posted by TurboFan

1. Start with a free body diagram, and it will start to work itself out. The sum of the forces must equal the mass multiplied by the acceleration. You can find acceleration with your motion equations - v(final)=v(initial) + .5*a*t^2. I think I remember that correctly...v(final) = 5m/s, v(initial)=-4m/s, t= 3 seconds. Solve for a.

Now setup the equation: f2*cos(theta)-f1 = m * a. Solve for theta.

2. F=m*A. m = 12,0kg, A= 9.81m/s^2. If nothing is moving, the force on the box from the floor must counter gravity exactly, so the force exerted on the box is 117.72N (newtons).

You've made my brain hurt tonight, and confirmed what I feared most - I've not consumed enough alcohol to counter the effects of college. My engineering mechanics are a little rusty, I may have just given you the dimensions for the playmate of the month.

I'm off to get a beer!

First one, I couldn't even set up the FBD. It was waaay to complecated to set them up and I didn't know what to put where. So, I gave up.

Second problem, I tried that. It was not 117.72 N. WTF...

Thanks for help anyways

zzinco79 · 10-03-2007, 11:13 PM

Quote:

Originally Posted by aequitas330

Reminds me of this....

Perfect example.

I'd give 100/100 on that.

TurboFan · 10-03-2007, 11:23 PM

Quote:

Originally Posted by zzinco79

First one, I couldn't even set up the FBD. It was waaay to complecated to set them up and I didn't know what to put where. So, I gave up.

Second problem, I tried that. It was not 117.72 N. WTF...

Thanks for help anyways

oops. I made a bad assumption. The cars are moving. The tension in the cable tells you that the car is in motion. If the cars were stationary, the tension in the cable would have been 14715 Newtons. I'm going to bed now. Sorry.

txusa03 · 10-04-2007, 07:50 AM

what is physics

10-03-2007, 10:36 PM	#1
zzinco79 Major 124 Rep 1,411 Posts Drives: 2006 BMW 325i Join Date: Nov 2005 Location: Rochester, NY iTrader: (8)	Physics Help!! No time to explain!! It is due by midnight!!! I tried them but it wasn't worked out Please help!! Attached Images __________________ 2006 BSM 325i / ZPP / ZSP / Adaptive Xenon / BLK leather interior / Steptronic Eisenmann racing / K&N Ram charger / M5 rep. wheels / D1S 6000k / Brex white ring / OEM style rear trunk spoiler / M steering / OEM strut bar / Blk line tail light Future Mod Hamann lip spolier / Mtech rear bumper
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10-03-2007, 10:50 PM	#2
canucklion pull my finger to get your kinder® surprise 148 Rep 10,455 Posts Drives: circles around you Join Date: Dec 2005 Location: Toronto, Canada iTrader: (9)	when in doubt, E= MC^2 that's how I (barely) passed physics 101 __________________
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10-03-2007, 10:53 PM	#3
zzinco79 Major 124 Rep 1,411 Posts Drives: 2006 BMW 325i Join Date: Nov 2005 Location: Rochester, NY iTrader: (8)	haha Yea.. I (barely) passed my physics 311 with F = ma. __________________ 2006 BSM 325i / ZPP / ZSP / Adaptive Xenon / BLK leather interior / Steptronic Eisenmann racing / K&N Ram charger / M5 rep. wheels / D1S 6000k / Brex white ring / OEM style rear trunk spoiler / M steering / OEM strut bar / Blk line tail light Future Mod Hamann lip spolier / Mtech rear bumper
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10-03-2007, 10:59 PM	#4
TurboFan Ski bum 317 Rep 6,198 Posts Drives: sideways Join Date: Aug 2007 Location: Knee deep in the pow iTrader: (8)	1. Start with a free body diagram, and it will start to work itself out. The sum of the forces must equal the mass multiplied by the acceleration. You can find acceleration with your motion equations - v(final)=v(initial) + .5at^2. I think I remember that correctly...v(final) = 5m/s, v(initial)=-4m/s, t= 3 seconds. Solve for a. Now setup the equation: f2cos(theta)-f1 = m a. Solve for theta. 2. F=m*A. m = 12,0kg, A= 9.81m/s^2. If nothing is moving, the force on the box from the floor must counter gravity exactly, so the force exerted on the box is 117.72N (newtons). You've made my brain hurt tonight, and confirmed what I feared most - I've not consumed enough alcohol to counter the effects of college. My engineering mechanics are a little rusty, I may have just given you the dimensions for the playmate of the month. I'm off to get a beer! __________________ 1999 e46 328i Ti Silver / Black[retired] 2007 e90 335xi Jet Black / Black[retired] 2011 e70 X5 35d Vermillion Red / Cinnamon 2011 e92 M3 LeMans / Fox Red extended
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10-03-2007, 11:05 PM	#5
aequitas330 Montego Blue FTW 56 Rep 1,110 Posts Drives: Montego Blue e90 328xi Join Date: Sep 2007 Location: Northeast iTrader: (0)	Reminds me of this....
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10-03-2007, 11:05 PM	#6
canucklion pull my finger to get your kinder® surprise 148 Rep 10,455 Posts Drives: circles around you Join Date: Dec 2005 Location: Toronto, Canada iTrader: (9)	^ I concur __________________
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10-04-2007, 07:50 AM	#10
txusa03 Major General 548 Rep 6,563 Posts Drives: TS330iPPSP6MT Join Date: Jul 2005 Location: Planet Earth iTrader: (3)	what is physics __________________ under construction!
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