Circuit Lab B/C

[Creationist127]

Not sure, but.... (Click to Show Hidden Text)

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?

(Click to Show Hidden Text)

 
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:

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?

[azboy1910]

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?

[Krish2007]

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?

Since no one else has answered (Click to Show Hidden Text)

1) R2, R1, R4, R6, R3, R5
2) Is=i2+i3+i8
3)-1.03*10^-35 N
4) Paramagnetism?   

[azboy1910]

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?

Since no one else has answered (Click to Show Hidden Text)

1) R2, R1, R4, R6, R3, R5
2) Is=i2+i3+i8
3)-1.03*10^-35 N
4) Paramagnetism?   

(Click to Show Hidden Text)

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. 

Your turn!

[Krish2007]

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.

[Umaroth]

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

[Krish2007]

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
Your turn!

[Umaroth]

Yikes I forgot to reply mb

An ideal Zener diode made of germanium is placed in parallel with a 330 ohm resistor, the two of which are placed in series with a 6V battery and 120 ohm resistor. The diode's breakdown voltage is 2.4V. (As you can tell from the JT invite test, I find Zener diodes interesting).
1) What is the current flowing through the 330 ohm resistor and the 120 ohm resistor if the diode is placed in forward bias?
2) Repeat #1 for a diode in reverse bias.

[azboy1910]

I am not sure about this, but,

Click to Show Answer

1. 50 mA through 120-ohm resistor, 0 mA through 330-ohm resistor
2. 13 mA through both resistors 

[Umaroth]

I am not sure about this, but,

Click to Show Answer

1. 50 mA through 120-ohm resistor, 0 mA through 330-ohm resistor
2. 13 mA through both resistors 

Click to Show Answer

1. Your mistake here is that you're assuming that the full 6V is applied across the 120 ohm resistor.
2. Your answer treats the diode as if it weren't there.
Start by treating the circuit as if the diode weren't there, and then add the diode and see what changes you have to make.