i'm solving electronic homework ,and i got the values R1=66.67
R2=12.4k
(and Rs=10 ,RL=1k are given),there is part in the question which want me to chose the closet values for the resistor before i design the circuit in pspice program.
can u tell me how i can chose from the given appendix below

Preferred resistance values (approximately 10% increase)

I1.01.52.23.34.76.8
II1.11.62.43.65.17.5
III1.21.82.73.95.68.2
IV1.32.03.04.36.29.1

I to IV for (+-)5% tolerance resistors
I and III for (+-)10% tolerance resistors
I for (+-)20% tolerance resistors

Values multiplied by 1, 10, 100, 1k, 10k, 100k, 1M, 10M
Multiplier 10 to 100k can cover all the preferred values
E.g. 11, 110, 1.1k, 11k, 110k

Resistor types: Carbon film, metal film, wirewound
i think this will be clear

I(1.0)(1.5)(2.2)(3.3)(4.7)6.8)
II(1.1)(1.6)(2.4)(3.6)(5.1)(7.5)
III(1.2)(1.8)(2.7(3.9)(5.6)(8.2)
IV(1.3)(2.0)(3.0)(4.3)(6.2)(9.1)

anybody have the answers for exam #00290201? I really could use the help … thanks a bunch.

1. Look at the circuit illustrated in Figure A-1. Assume that the values of R1 and R2 are equal. If you connect your meter’s test probes to points A and B in the circuit, which of the following voltages would you measure?
A. 9 V
B. 6 V
C. 3 V
D. 0 V

2. In the circuit shown in Figure A-1, where would you connect your meter’s test probes to measure the full battery voltage?
A. To points D and E, or to points B and E
B. To points A and C only
C. To points D and E, or to points A and C
D. To points B and E only

3. In the circuit shown in Figure A-1, suppose that the value of R1 is 100 kW and the value of R2 is 470 kW. At which of the following locations in the circuit would you measure the highest voltage with your meter?
A. Between points A and C
B. Between points A and B
C. Between points B and C
D. Between points B and E

4. In the circuit shown in Figure A-1, suppose that the value of R1 is 500 kW. In order to obtain a multimeter reading of 1 V between points B and C in the circuit, the value of R2 would have to be
A. 10 kW.
B. 100 kW.
C. 1,000 kW.
D. 10,000 kW.

5. Imagine that you’ve properly connected your multimeter into an operating circuit, and the meter’s function/range switch is set to read DC voltage in the 20 V range. The meter displays a “1″ in the most significant digit position. This indicates that
A. the meter measured a voltage of 1 V at the point under test.
B. the power to the circuit is turned off.
C. the voltage at the point under test is greater than 20 V.
D. the function/range switch should be set to the next lowest range.

6. Silver has the highest conductivity rating of any common metal. Which of the following correctly ranks metals in decreasing levels of conductivity?
A. Silver, zinc, gold, platinum
B. Silver, copper, aluminum, lead
C. Silver, gold, nickel, mercury
D. Silver, copper, gold, aluminum

FIGURE A-2—Use this illustration to answer Questions 7, 8, 9, and 10.

7. Look at the circuit shown in Figure A-2. Switch S1 is open as shown, and R1 and R2 each have a value of 100 kW. If you connect your meter’s test probes to points A and B in the circuit, what voltage would you measure?
A. 9 V
B. 6 V
C. 3 V
D. 0 V

8. For the circuit shown in Figure A-2, the correct procedure for measuring the resistance value of R1 is to
A. connect the multimeter between points C and D and measure the resistance with switch S1 open.
B. connect the multimeter between points C and D and measure the resistance with switch S1 closed.
C. connect the multimeter between points D and A and measure the resistance with switch S1 open.
D. connect the multimeter between points D and A and measure the resistance with switch S1 closed.

9. You’re using your meter to make voltage measurements in the circuit shown in Figure A-2. Your meter is connected between points A and C, and you’re getting a reading of 6 V on the display. What can you conclude from this reading?
A. Switch S1 is open.
B. Resistor R2 has a resistance value that’s twice the value of either R1.
C. Switch S1 is closed.
D. Resistors R1 and R2 have equal resistance values.

10. In the circuit shown in Figure A-2 where R1 and R2 have equal resistance values, when switch S1 is closed, what voltage would you measure across R2 with your meter?
A. 0 V
B. 1 V
C. 3 V
D. 6 V

11. What important safety precaution must be observed when measuring resistance in an electronic circuit?
A. All power to the component under test must be disconnected.
B. The meter’s highest resistance range setting should be used until the actual value is determined.
C. The black test lead must be connected to the chassis ground.
D. The red test lead must be at the most positive point in the circuit.

FIGURE A-3

I’m pretty new to electronics, but i know a but about it. I recently opened up my door bell transmitter (the thing that is outside that u press to make ur door bell ring). its wireless. inside i found the average array of ceramic capacitors and resistors. but there are 3 things i have trouble figuring out. There is somethin that is labeled as d1 (kinda like how resistor is labeled r1,r2,r2 and capacitor is c1,c2, etc.) im guessin this is a diode? not sure. it just makes sense to me. then, there is a blue round thing that kinda resembles an aluminum capacitor but its not. its located near a long metal bar. my guess is that this is the transmitter? and the bar is an antenna? no idea. and final thing is in the center of the circuit board. its like a black drop of some sort of material. its not like an electronic component. it looks like a drop of black glue thats hard and solid. on the underside u can see a bunch of circuits ending under it. my guess is that it connects them all, but that doesnt seem right. i honestly cant figure out wat it could be. sigh… well plz let me know wat all this stuff is. i really wanna build a similar contraption. thnx a lot guys

I know how to start and all the basics, but then how do I declare the fractions and how to write the formula?

Write a program that finds the resistance of an electronic circuit with three parallel resistors resistor1, resistor2 and resistor3. The resistance can be computed using the following formula:

resistance = 1/((1/resistance1) + (1/resistance2) + (1/resistance3))

I use C++ visual….

many thanks!
videobobkart, thx for answering!! my problem is how to write the formula in c++ especially that it contains fractions…here is what I'vd done (I know it contains lots of errors):
#include<iostream>
void main()
{
int r1,r2,r3;
float r;
std::cout<<"enter a value for r1";
std::cin>>1>>/>>r1;
std::cout<<"enter a value for r2";
std::cin>>1>>/>>r2;
std::cout<<”enter a value for r3”;
std::cin>>1>>/>>r3;
r=1/((1/r1)+(1/r2)+(1/r3))
std::cout<<"resistance ="<<r;
}
oh and again I use Microsoft visual c++ 6.0
how do i declare the "fraction" sign?

R3 and R4 are in series with one another and are both in parallel with R5. This parallel combination is in seires with two series-connected resistors, R1 and R2. R1= 2.5 kilo ohms R2=10 kilo ohms R3= 7.5 kilo ohms R4= 2.5 kilo ohms R5= 2.5 mega ohms and VS= 100V
sorry.. total resistance
total currecnt
voltage across serious resistors and parallel combinations
current through each resistor

thank you..
okay i got the total resisitance of 9.99 by doing 1/.1000005 and now im working on current.. V = I x R
I= R/V
I=22.5/100
i=.22 ?

i'm struggling with this question ,i couldnt find the value of R1 and R2 and if u have any info about how i can use pspice program plz tell me
the question details is inside the file below.

http://www.freewebs.com/radicalfunction/Questions.doc

plz help me