# Search results

1. ### Non-composite beam analysis

Hi, normally when we try to analyse a structural beam with composite section, we apply transformed section method or so. But what if two beams are just put together (one onto another one) instead of having a composite relation (e.g. glued together), how am I going to analyse the forces and...
2. ### Size of specimen and compressive strength of concrete

Hello everyone. I have a question about compressive strength of concrete. It is said that (in my country) 150 mm x 150 mm x 150 mm concrete cube is used for concrete testing. Someone asks me why 100 mm x 100 mm x 100 mm is not used. In fact, I know that sometimes it is allowed or even prefered...
3. ### Comparator design using a 4-bit adder

And you mentioned that there should not be Cin? Does this mean there are no cascading inputs?
4. ### Comparator design using a 4-bit adder

I have a question about the XOR gates. Are those XOR gates for doing 2's complement (i am thinking in this way)? But I know that 2's complement is not just inverting 1 and 0, but also needs to add 1 after that. It seems that the above design cannot do that?
5. ### Comparator design using a 4-bit adder

A truth table looks like this? because I have never drawn a truth table for such a design...so I searched on google...
6. ### Comparator design using a 4-bit adder

I think it should be using 2's complement.
7. ### Comparator design using a 4-bit adder

Homework Statement Hi, it's me again. Now I am going to design a 4-bit magnitude comparator using just ONE 4-bit adder and infinitely large number of gates (AND, OR, NOT, NAND, NOR, XOR, XNOR) for signed numbers (negative binary). Homework Equations A > B => A3barB3 + A2barB2x3 +...
8. ### Op-amp as a comparator (analog-to-digital conversion)

Homework Statement Okay, This time it's an exam question. I am doing some past papers and there are questions about comparators which are not introduced in this course (this course is preliminary course for engineering students who are interested in electrical, electronic or computer...

10. ### Probability question on fair coin

then 1 - 0.52 = 3/4
11. ### Probability question on fair coin

so the probability of getting HH is p2? Then the required probability is 1- p2?
12. ### Probability question on fair coin

If it is HT, then no matter the next one is T or H, TH already occurs before HH, right? If it is TT, then also no matter the next one is T or H, TH already occurs before HH, right? If it is TH, then obviously no matter the next one is T or H, TH already occurs before HH, right? Just the case if...
13. ### Probability question on fair coin

so if there is no HH, then it is alright? Let the probability of getting a H be p. Then the required prob. is 1 - p2?
14. ### Probability question on fair coin

Actually TT, HT,TH all means TH must occur before HH, right?
15. ### Probability question on fair coin

Should I indeed use conditional probability? In case I have a T at the 1st trial, then it already achieves the event that TH appears before HH?
16. ### Probability question on fair coin

Oh Sorry... I have a typo in the question... The correct question is "T,H before HH"
17. ### Probability question on fair coin

but it seems 0.5*0.5*0.5*... , gets you 0...

1?
19. ### Probability question on fair coin

Which two? TH and HT? 0.5*0.5 + 0.5*0.5 = 0.5?
20. ### Probability question on fair coin

So simply calculate the first case?

Same?
22. ### Probability question on fair coin

I don't quite understand your question... The prob. of getting a head or a tail is 1/2? Is this what you are asking?
23. ### Probability question on fair coin

Homework Statement A fair coin is continually flipped. What is the probability that the pattern T,H occurs before the pattern H,H, where T and H respectively denote Tail and Head of a coin? Homework Equations Prob. = (n r) (pr)(1-p)n-r The Attempt at a Solution I am thinking whether the...
24. ### Probability and normal distribution

because question 1 is P(acceptable)...so I use it directly...
25. ### Probability and normal distribution

So is this P(more than 2 tests) = 1 - [ P(1st acceptable) + P(1st rejected, 2nd accpetable) ] = 1 - [ p + (1-p)p ] wrong?
26. ### Probability and normal distribution

I understand 1st and 3rd question now. For 2nd question, my approach now is let p be the P(accpetable) in 1st question. P(more than 2 tests) = 1 - [ P(1st acceptable) + P(1st rejected, 2nd accpetable) ] = 1 - [ p + (1-p)p ]. Is this correct?
27. ### Probability and normal distribution

Homework Statement Due to the pollution from the industry around an apple farm, the apples grown there may be contaminated by heavy metals. It is believed that the amount of heavy metals in an apple of the farm follows the Normal distribution. N(16,16) which has a mean μ = 16 units and σ = √16...
28. ### Prove arcsin x for its logarithm form

Homework Statement Given sin x = (eix - e-ix) / 2i, I want to prove that arcsin x = -i ln(ix + √1 - x2) Homework Equations I know about the Euler's formula and complex number. But I have never learnt about complex logarithms. The Attempt at a Solution I try to use x = sin y. But it seems...
29. ### Decomposition using roots of unity

Sorry. My typo... It should be (e2πi/5)5, so it equals 1.
30. ### Decomposition using roots of unity

I can solve it now. Thanks.