coach94

Two wooden crates rest on top of one another. The smaller top crate has a mass of m1 = 17 kg and the larger bottom crate has a mass of m2 = 92 kg. There is NO friction between the crate and the floor, but the coefficient of static friction between the two crates is μs = 0.8 and the coefficient of kinetic friction between the two crates is μk = 0.62. A massless rope is attached to the lower crate to pull it horizontally to the right (which should be considered the positive direction for this problem). 1) The rope is pulled with a tension T = 248 N (which is small enough that the top crate will not slide). What is the acceleration of the small crate? 2.275 m/s^2 2) In the previous situation, what is the frictional force the lower crate exerts on the upper crate? 38.675 N 3) What is the maximum tension that the lower crate can be pulled at before the upper crate begins to slide? 854.56N 4) The tension is increased in the rope to 1223 N causing the boxes to accelerate faster and the top box to begin sliding. What is the acceleration of the upper crate? 6.076 m/s^2 5) As the upper crate slides, what is the acceleration of the lower crate? this is the only one that I could not figure out I know all my answers for 1-4 are correct but i cant seem to get the answer to 5. If someone could help me with an equation it'd be appreciated edit: QUESTION HAS BEEN RESOLVED

alright cool thanks for the help man appreciate it

oh okay so its fine how i have it written then

what do you mean by not combined?

cool thanks! one last question though, would the truth tables look something like this? W's DC|X <- x because it goes through X right 00|0 01|1 10|1 11|1 X's WV|F <- F because this is where F is derived? 00|0 01|0 10|0 11|1 V's BA|X <- x because it goes through X right? 00|0 01|1 10|1 11|0 my professor never taught us how to construct them so im trying my best to go from the book but im not too sure

Sorry im working on multiple things at once i mis-read my own question (D+C).(B(xor symbol)A) should be correct now id think

I think ive figured it out. (D+C) <- would be W (B.A) <- would be V and to put them together tying in the xor the final expression would be (D+C) (xor symbol) (B.A) ? i think that would be right?

woops forgot a key piece of information haha! W is an OR gate, X is an AND gate, V is an XOR gate

I have this diagram I am trying to find the boolean equation for this. I know (d+c)(ba) I dont know how to write the equation to include the box X anyone give me a hand?

would you be able to check if im going in the right direction with this? Just want to make sure I got the first one done correctly i have about 30 more to do lol. from the whole example i provided, i got B+D'C'+D'+C' actually cant you combine it to be B+D'+C'

but wouldnt A+A'=1 imply that those a's would be 1? and for the 4th and 5th terms it would go D'CB(A+A')? which would be D'CB?

So what I got from the last two would be DC'B'A' + DC'BA = DC'B' + DC'B = DC' + DC' = C'(D+C)?

1. means or 2. correct 3. yes 4. no just underlined it just because ( probably shouldn't do that ) Now when Im doing this, can i take say an A' from the second set of terms and match it with one from lets say the second to last set of terms? Do i have to go in a specific order? And do the rules apply to other variables the same? or do they work just as a or b?

(A+A') would be 1 right?

I've seen those rules a few times before, But i dont see how they will help me when I have 4 variables not just 2 or 3?