## Circuit Lab B/C

Creationist127
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### Re: Circuit Lab B/C

azboy1910 wrote:
September 16th, 2020, 7:43 am
Creationist127 wrote:
September 16th, 2020, 5:37 am
azboy1910 wrote:
September 15th, 2020, 12:32 pm

1a. 0.025 s
1b. 0.0044 s for 1 volt across the capacitor. 0.0198 s for 4.5 volts across the capacitor.
1c. 0.0395 s

2. A?

3a. 25 megaohms, tolerance of 5%
3b. 19 kilohms, tolerance of 10%
3c. 4 kilohms 
1. a. is right, but I got .0029 s and .017s for b., and I was looking for infinite time or something similar for c., as in an ideal system the capacitor will only approach, and never reach, fully charged.
2 is right, 3. a. and b. are right. 3. c. the numbers are right, but I've always seen that no fourth band means a tolerance of 20%.

Which one of us did 1. b. and c. wrong?

Ok, so this is how I came up with my answers for 1b.

1b. 1 V/(63.2% x 9 V) x 0.025 s = 0.0044 s, 4.5 V/(63.2% x 9 V) x 0.025 s = 0.0198 s

This is most likely wrong, but this is just how I got my answers.

1c. I think you are right for this one because capacitors never really accomplish being fully charged as you said, although very close.
Aha! RC circuits have their own equation:
$V_t = V_{max}(1-e^{\frac{-t}{R*C}})$
In this case, you plug in 1 or 4.5 for Vt, 9 for Vmax, and .025 for R*C, and solve for t, where (if I did it right) you should get .0029 and .017, respectively. Good try, though! Your turn.
EDIT: Just out of curiosity, where did the 63.2% come from?
Last edited by Creationist127 on September 16th, 2020, 8:27 am, edited 1 time in total.
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### Re: Circuit Lab B/C

The 63.2% is how fully charged a capacitor is after 1 time constant. Multiply that by 9, and you get the voltage across the capacitor after 1 time constant (I think it was like 5.68 V or something). Anyway, you're right about that, I should've probably just used the equation to solve for the time.

Ok,

1. Rank the resistors in order of voltage from greatest to least.

2. Write an equation for current Is in terms of i2, i3, i6, and i8.

3. A proton and an electron are 50 mm apart. Find the magnitude of the electrostatic force between them.

4. What type of magnetic property does the metal copper exhibit?
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Krish2007
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### Re: Circuit Lab B/C

azboy1910 wrote:
September 16th, 2020, 8:58 am
The 63.2% is how fully charged a capacitor is after 1 time constant. Multiply that by 9, and you get the voltage across the capacitor after 1 time constant (I think it was like 5.68 V or something). Anyway, you're right about that, I should've probably just used the equation to solve for the time.

Ok,

1. Rank the resistors in order of voltage from greatest to least.

2. Write an equation for current Is in terms of i2, i3, i6, and i8.

3. A proton and an electron are 50 mm apart. Find the magnitude of the electrostatic force between them.

4. What type of magnetic property does the metal copper exhibit?
1) R2, R1, R4, R6, R3, R5
2) Is=i2+i3+i8
3)-1.03*10^-35 N
4) Paramagnetism?

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azboy1910
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### Re: Circuit Lab B/C

Krish2007 wrote:
September 19th, 2020, 9:59 am
azboy1910 wrote:
September 16th, 2020, 8:58 am
The 63.2% is how fully charged a capacitor is after 1 time constant. Multiply that by 9, and you get the voltage across the capacitor after 1 time constant (I think it was like 5.68 V or something). Anyway, you're right about that, I should've probably just used the equation to solve for the time.

Ok,

1. Rank the resistors in order of voltage from greatest to least.

2. Write an equation for current Is in terms of i2, i3, i6, and i8.

3. A proton and an electron are 50 mm apart. Find the magnitude of the electrostatic force between them.

4. What type of magnetic property does the metal copper exhibit?
1) R2, R1, R4, R6, R3, R5
2) Is=i2+i3+i8
3)-1.03*10^-35 N
4) Paramagnetism?

1. Correct
2. You could also do Is = i2 + i3 + (i6 - i6) + i8, which also simplifies to Is = i2 + i3 + i8, so this is also correct, but I just wanted to point this out. I made a mistake asking this question, asking i6 to be part of the total current equation for Is, so I apologize.
3. The magnitude here is just the absolute value of the electrostatic force, which is 1.03 * 10^-15 N.
4. The metal copper exhibits the magnetic property of diamagnetism, not paramagnetism. 
Last edited by azboy1910 on September 19th, 2020, 10:10 pm, edited 1 time in total.
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Krish2007
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### Re: Circuit Lab B/C

1) Simplify the following boolean statements as much as you can using boolean algebra (! means not)
a) A+1
b) A*1
c) A*0
d) A+0
e) A*!A
f) A+!A
g) A*B+A*!B+AC

2) What does MOSFET stand for?

3) Find the equivalent resistance between points A and B.
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Umaroth
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### Re: Circuit Lab B/C

1) a. 1
b. A
c. 0
d. A
e. 0
f. 1
g. A
2) Metal Oxide Semiconductor Field Effect Transistor (I mosfets!)
3) 10 ohms
Last edited by Umaroth on September 20th, 2020, 8:54 pm, edited 3 times in total.
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Krish2007
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### Re: Circuit Lab B/C

Umaroth wrote:
September 20th, 2020, 8:42 pm
1) a. 1
b. A
c. 0
d. A
e. 0
f. 1
g. A
2) Metal Oxide Semiconductor Field Effect Transistor (I mosfets!)
3) 10 ohms
All correct, though I would like to add MOSFETs are also known as Metal-Oxide-Silicon Field-Effect Transistors