# Search results

3. ### Four Clocks Problem

You are absolutely correct. :) Btw, here's my take on the christmas tree problem... Let the blue, red and white balls be labelled A, B, C, respectively. Weigh A1+B1 against A2+C1. If A1+B1 == A2+C1, weigh A1 versus A2. If A1 > A2, then the heavier balls are A1, B2 and C1; otherwise, it is...

5. ### Coin weightings with two irregular coins

I think I am able to get it in 4 weighings (but not less). The initial steps are as follows: Assuming that the coins are labelled 1 to 8, then the initial weighing is 12vs34. If 12=34, then the second weighing is 156vs278. Otherwise (whether 12>34 or 12<34), the second weighing is 137vs248...
6. ### Diagonal Garden Path

Oops, it should have been: Remove the path (say of length x) from the garden, we have the area equation (55)(40) - x = \sqrt{x^2 - 40^2} (40) and that gives x = 66.67 yards.
7. ### Diagonal Garden Path

Answer is hidden. Remove the path (say of length x) from the garden, we have the area equation (55)(40) - x = 2 \sqrt{x^2 - 40^2} (40) and that gives x = 48.202 yards.

9. ### 12 balls

I am pretty positive the bolded part would not work.
10. ### Help me solve this

Happy New Year to you too; yes, after much experimentation with 'staircase' cuts and with the initial assumption that the 8x1 is located at the center of the room.
11. ### Help me solve this

Solution hidden below. As a hint, the 8x1 is placed exactly vertically at the center of the room. :) 1. Cut the 10x10 into 2 portions. AAAAAAAAAB AAAAAAAAAB AAAABAAABB AAAABAAABB AAABBAABBB AAABBAABBB AABBBABBBB AABBBABBBB ABBBBBBBBB ABBBBBBBBB 2. For portion A, move the whole...
12. ### Can you solve this?

Answer is hidden. The probability of getting n heads and (N-n) tails in N toss is P(n) = \binom{N}{n} (0.5)^N and the corresponding multiplier of gamble is X(n) = (1.5)^n (0.6)^{N-n} = (0.6)^N (2.5)^n The mean of this measure is E{X} = \sum_{n=0}^N P(n) X(n) = (0.3)^N \sum_{n=0}^N...
13. ### MATLAB MATLAB: Using WavWrite to Create a Single Audio File

You could do this... xbuff = []; for k = 1:(the number of tones) x = (insert your function here); xbuff = [xbuff; x(:)]; end sound(xbuff,fs); wavwrite(xbuff,fs,bits,'audio.wav');
14. ### Node Analysis

No mistakes alright.
15. ### Finding impulse of a CT system

Express the convolution as an integral. Compare this integral with the problem statement and obtain a function of the form h(t-\lambda). It should not be too difficult then to determine h(t).
16. ### Engineering Simple RL circuit

I think it is more of the latter, that the 2H inductor is not charged before t = 0. My reason for saying so is as follows: The voltage across the 2H is always 0V before the switch opens. Then Ldi/dt = 0, or in other words, there is no change in the current across this inductor, hence it remains...
17. ### MATLAB Whats wrong with this matlab code?

Here's a screenshot...
18. ### Need L and C to be in series in order to have a RLC series circuit?

Strictly speaking no, the R should be in series with L and C too. Then again, an R which is in parallel to the LC pair could be converted (with network transformation theorems) to being in series to it. So I guess there is really no straight answer to this question.
19. ### MATLAB Whats wrong with this matlab code?

I have copied-and-pasted the script on the Matlab (R11.1) command prompt and a figure appears. Nothing appears in the command line though. How did you try to run the script?
20. ### Quick Thevenin Equiv Question

Yes, the method is applicable on all type of circuits.
21. ### Quick Thevenin Equiv Question

3. Deactivate all independent sources. Insert a voltage source Vs between AB and measure the resultant current I; then RTh = Vs/I. Alternatively, insert a current source Is between AB and the resultant voltage V is measured; RTh = V/Is. You may choose any nonzero values for Vs and Is, e.g. Vs =...
22. ### Capacitor Lab - Charging/Discharing Paths

My thought concurs with AlephZero and I believe the expression for the charging time constant is ((R1+Rs)||R2)C.
23. ### MATLAB Matlab Help Archimedes Method

Before you even start to use Matlab (or any other computing tools) to solve the problem, you should at least have a plan in mind about the approach/method to use. You asked about how Matlab can be used to solve the problem; well, tell us something about your plan (a pseudocode or the sort)...
24. ### How do these resitors not affect the voltage

Since the resistors are connected in parallel to the voltage source, they do not affect the rest of the circuit voltage-wise (unless of course their resistances are set to 0).
25. ### Finding the voltage

I don't see any mistakes on your part. But I got a slightly different answer in v0 = (-0.19853)*12 = -2.3824A.
26. ### Engineering One Term is missing for Circuit Analysis Help to Solve it?

Whoops. I meant the (v3-v2)/1k current.
27. ### Engineering One Term is missing for Circuit Analysis Help to Solve it?

You have missed out the (v3-v1)/1k current when you took the KCL on supernode 3-4. Apart from that, due the to 20V source, node 4 and the reference node will form a supernode, hence you'd have a (super-)supernode 3-4-ref. Try again.
28. ### Simple Nodal Analysis

No, v4 is not 8V, but either one of (v4-v3) or (v3-v4) is and it is not difficult to figure out which one is. The nodal equation for node 4 is incorrect. Please check that against your first post. You have above 3 equations with 3 unknowns (v2, v3, v4). It becomes thus a mathematical problem...
29. ### Simple Nodal Analysis

So far it's correct. Try clicking on the (thumbprint) image to view a larger one.
30. ### MATLAB Matlab question

I think repmat() is what you need. Type help repmat at the prompt for instructions on the use.