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disruptors
Nov14-04, 11:15 PM
Hey ppl, sorry I was just wondering if anyone knew how to do the question i posted earlier(TWO BLOCKS AND TWO PULLEYS), as I have to submit it and cannot figure it out still!?

Thanks...

tiger_striped_cat
Nov14-04, 11:43 PM
can you post a picture of it. I'm having trouble picturing this system.

disruptors
Nov14-04, 11:53 PM
here's the pic, thanks

tiger_striped_cat
Nov14-04, 11:55 PM
where? I dont see it as part of your post

disruptors
Nov15-04, 12:03 AM
oh sorry tiger, its okay i had to submit it, thx for your time...i cant get the pic up for some reason..

disruptors
Nov15-04, 12:04 AM
never mind must have been my browser

tiger_striped_cat
Nov15-04, 12:26 AM
well how did you do the first part? it looks right to me. you did:

\sum{F} = ma

always always ALWAYS start with this over and over again (or at least try to strat with this). The right hand side will have only ma or 0 thats all it will ever have ( and zero is a particular case of ma--when it is not accelarating, that is, not moving, or constant velocity) The left hand side just sums your forces. So after picking your postitive and negnative on your x and y axis (always do this too) and drew your free body diagram (I hop you did this) you must of did:

T + T = m_2a_2

And then you solved for T

Now for the next part do the same thing

1) Draw FBD
2) \sum{F} = ma
3) T - m_1g = m_1a_1

And then solve for a_1 in terms of everything else they gave you