Im stuck on this problem on our online physics problems on masteringphysics. Any help is greatly appreciated. This is my last effort please reply with suggestions or if you know the answer. It's an atwoods machine type problem.
Physics HW help
Im stuck on this problem on our online physics problems on masteringphysics. Any help is greatly appreciated. This is my last effort please reply with suggestions or if you know the answer. It's an atwoods machine type problem.
dude sorry to say, but, that sucks... I don't look forward to physics...
5.238
Val for President
damn it's been a long time cuz i don't remember this shit at all, goodluck w/physucks
I think it should be -9.8 m/s^2
According to the first part of the problem, the system is at equilibrium (all net forces are zero) just from the force of friction from block A. This means that friction from block A is exerting a force equal in magnitude to gravity.
Part two is doubling the mass of block A which doubles the amount of friction. Twice the friction = twice the force pulling on block B.
(So, if you pushed block B down it would immediately start to slow down/decelerate until it stopped.)
Since we know that friction was equal to the force of gravity in the first one, (which reduced the 9.8 m/s^2 acceleration due to gravity to zero), then doubling the friction will reduce it an additional 9.8 m/s^2... making the acceleration -9.8 m/s^2
The tricky part is how to answer the question. The problem asks for a magnitude... which is a scalar quantity. Scalars don't (usually) have negative values. Technically the correct answer should be 9.8 m/s^2 (without the negative sign), but your prof might want you to put the negative sign to demonstrate that you know block b is decelerating
Give me a second
[/brain explodes]Originally Posted by Tarzanman
lol please dont bring back memories from physics class i sooooooooooooo hate that shit
Okay, I just checked my mastering physics hw and it wont let me go that far back. I finshed all the HW last week, so it would only let me go back to chapter 6. Either way, At the house, I have a bootleg cd with all the problems and answers. I'll give you the answer tomorrow but $40 if you want cd.
Ya'll are wrong k is anumber usally smaller than 1 and has no units what book are you using? i have the soulitions guide from university physics.
Physics volume 1 by Randall D. Knight
-9.81 m/s^2 is the V
I checked the book its problem 30 in chapter 5
What book is that the problem number because thats not the one from our book.
University Physics, Volume 1, 11th edition (Young & Freedman)
You should buy my cd
Havn't gotten it yet guys please continue trying . It must include for sure variables wA and gravity. Other then that im lost. If you have the answer snail i would appreciate it greatly. Its magnitude of acceleration.
Like I said, I will get you the answer tomorrow. I am sleeping at a freinds house, Im on beer #9 so I cant drive home. Im guessing it is due tomorrow? Well dont worry about it being late since it takes off minimal points being 5-10hrs late. Better 90% then 0%
Its due by 1pm tomorrow any help is greatly appreciated.
SOLVED thanks for all the help guys. Here is the answer for the curious
(wB*g)/(2wA+wB)=Magnitude of acceleration
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