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Well i have a question:

Here it is my circuit

The circle with the arrow is an npn transistor

why when i increase the value of R1 and voltage drop  in R2 gets bigger?

well im having this trouble for several days.

where am i wrongThe circle with the arrow is an npn transistor
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Learn the most important control and control categories that every architect and developer should include in their projects.

I have a circuit with a transistor and a light emmiting diode:

My source voltage is 11.6 volts

My transistor is in series with 2 resistors and the light emmiting diode.

The resistors values are 1000 Ohm each.

The base is connected to a 0.7 volt supply.

Voltage drop in resistors is 2.7 volts each.

The voltage drop in the light emmiting diode is 2.7 volts

Why is there a 3.4 V voltage drop between emmiter and collector?Shouldnt it be 0 and the voltage drop in the resistors be (11.6-2.7)/2 volts ?

What am i missing?

Need help with a formulas to calculate:
1. (Cell DM23) Most recent past 6-week run rate of 52 week historical data that excludes zeros and high- low numbers (seasonality/Standard Deviation > X).
2.  (Cell DN24) Return data in Range $BM$22:$DL$3171 in column DN depending on current week written in Cell DM16

(see attached file)
Well i would like some help here:

A semiconductor's resistance is relevant to its impurities . The p-type doped region in an NPN transistor is very thin.So Why many electrons pass through from the emmiter to the base since base resistance is very big?
I need to learn embedded software and hardware development life cycle and use it to create electronic hardware/software component.  I need to approach this job systematically.  For example, what is the order of tasks.  Probably requirements should be gathered and documented.  Then, what's next and so on?  At what stage should we select hardware components.
How to simplify this probability expectation, where X Y Z are 3 random variables.

E[ E[X | Y,Z] | Z ]

I don't recall what the comma means in this expression. I started reviewing probability over a year ago , but work keeps getting in the way, and I am not even sure when I learned about a comma in an expectation expression. Before helping me simplify, could you show me an online definition of the comma in an expectation expression. Once I understand the definition, maybe I'll be able to simplify it.

Thanks in advance.
The demand of IT service is a random variable (X) having the Poisson distribution μ=3.4. The cost of producing each pizza is 20 and each is sold at selling price of 40.
Suppose 5 pizza are made daily, no pizza is reserved for next day. Find the expected total profit daily.

p(0) x -100 + p(1) x -60 + p(2) x -20 + p(3) x 20 + p(4) x 40 + p(>=5) x 100

My answer = 27.1004. Suggest ans = 27.118.

Do I miss anything ?
I have an index and it is only published quarterly. I want to change it to monthly data.  I did the to the power 1/3 so each month in the quarter has the same return and it produces the same return as the quarter. This causes correlation problems with other indices which has monthly data.

Index 1 (Quarterly Data)
Index 2 (Monthly Data)

Index 1
Quarterly Return 0.48%

Index 2
June -6.71%
July 1.29%
August 2.65%
Which bring this quarterly return to -3.00%.

When I am converting Index 1 to monthly data , i would like to use Index 2 as a guidance.  So, it needs to weighted using the Index 2 data when making Index 1 monthly.

I tried the following.

For June Index 2 x1 = (1+ -6.71%)/(1+ 3%) - 1
For July Index 2 x2 =(1+ 1.29%)/(1+ 3%) - 1
For August Index 3 x3 = (1+ 2.65%)/(1+ 3%) - 1

For June Index 1  y1= (x1/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)
For July Index 1 y2= (x2/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)
For August Index 1  y3= (x3/(x1+x2+x3)) * 0.48%        (0.48% is the quarterly return for Index 1)

Then when I compound (1+y1)(1*y2)(1*y3) - 1 = 0.48% So it worked for this quarter.

It works great for some quarters but it doesn't work for some quarters. In some quarters, when I compound y1 y2 y3, i get a number very different from the actual quarterly data for Index 1.  Please see the attached file for the excel file. It has the calculations.
Attached are few pages from Image Signal Processing textbook.  It talks about how image is acquired from pinhole  Camera model.

They come up with Two equations from matching similar triangles.  Please identify the similar triangles.  And how they come up with Two equations from similar triangles?

My question is in following line of section 1.2.1
"By matching similar triangles we obtain the relations"
y = -f * (Y / Z)     and     x = -f * (X / Z)
Hi I have a problem, I'm trying to solve for x,
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Develop a strong foundation and understanding of web design by learning HTML, CSS, and additional tools to help you develop your own website.


Is there a way to calculate percentile rank using a conditional statement. For example, PERCENTRANK.EXC of column Ratio if Rating value is AAA. Example is attached.


I am unable to understand how we can derive: (S,K and cap are positive integers)

3*( max(S-K,0) – max(S – (K+Cap/3),0))


3* min(max((S – K,0), Cap/3)

From plugging values in 3* min(max((S – K,0), Cap/3) , I can see that it is equivalent. But how do i think about this?

Water molecules can be joined by hydrogen bounds. Should be these clusters calculated as one particle? Is there any theory that can estimate the numbers of all particles (moles) per one kilogram of pure water? Is it possible to calculate also the distributions of the water molecules through these clusters? E.g. number (moles) of clusters composed with two molecules of water.
I have a set of points and if I draw them on a paper, I have a diagram like the image in attached file.
I want to find any almost horizontal curve/line in the scattered points, something like another image in the attached files, the image with red diagram.
the result will be like below image:

In fact what I want as output is an array of points that are on the line/curve, or the equation which gives me the y component of the point if I set the x value.

I searched for a Java/Android library or code that does the job but didn't find any. I would appreciate if you let me know about the exact mathematical process or any Java/Android library or class that does the job.

Thanks in advance.
Dear experts,

The below url shows the compound interest calculations - discrete and continuous.


In the video between time lines 6.45 minutes - 7.05 minutes, it shows log 2/0.05 = 11.55 yrs

If log 2 to the base 10 gives 0.3010. Then 0.3010/.06 = c5.016. How is the number 11.55 arrived?

Is it considering log 2 to the base 'e'?

then in which cases do we calculate log use base 'e'?

Thank you

Kindly help.
Hi to all,

I use findpeaks function in my code to calculate the four maximum values of a fft function.

I use it in this way:

[maxpeaks, idx] = findpeaks(10*log10(psdx),'MinPeakDistance',195,'NPeaks',4,'MinPeakHeight', -Inf, 'SortStr','descend')

Open in new window

The problem is that I need to run the code in a Matlab version which doesn't have the Signal Processing Toolbox. Is there any solution to write a similar function without the need of the SP Toolbox?

Thank you!
Hello! I am trying to figure out (am I am completely new to Livecycle) how to track an employees time they spent traveling whether it be in one day or for overseas folks multiple days, and either find the time duration or adding the estimated time it takes for each segment of their trip in order to calculate the time our of their normal work hours they are eligible for time compensation. I cannot decide if its easier to do a duration between two times or do like the previous form in excel , and calculate with decimals. After the time duration is calculated, they will enter in either decimals or mins, the time it takes to get from their home to work and it will be subtracted from the total hours they spent traveling. I have been searching for formulas to do this but I don't have an experience with javaspript or formcalc. When someone does post a formula I have no idea how to implement it into livecycle. Thanks!
I would like to perform fractal analysis on a financial series (stock exchange index). What shall I use (prices or log returns) for calculating fractal dimension, Hurst Exponent, for performing R/S Analysis and for predictions? Are there R functions that calculate all of these immediately? Are there any things I need to take care of when analyzing the index? Thank you in advance!
At the time of Solving the angle dependence with time for a simple pendulum without taking approximation i got a 2nd degree Differential equation After integrating for one time i got a constant and took It as m and end up with another Integration and lost My Hope over It.
Integral of one over Square root of (m+cosx) last Hope that one may say how to solve this 😖😖
OWASP: Forgery and Phishing
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While learning about converting numbers to hexadecimal, I found a video that seems to explain it good. I understand most of it. But could someone explain why a number like one (1) divided by 16 produces 0 with a remainder of 1?
5815 / 16 = 363 R 7
 363 / 16 = 22  R 11 (B)
  22 / 16 = 1   R 6
   1 / 16 = 0   R 1
Result = 16B7

Open in new window

I'm trying to calculate fastener load for a shelf of the given dimensions below.

|               20.5"

This is an L shelf with the load being placed on the bottom portion

For the moment let's assume the materials used are able to support the required load. I am fully aware that I need to evaluate the materials used, bracing, and sizing, etc.  This is really just a starting point.  My goal is to create a "floating shelf" where the rear brackets will be hidden by the load.

 I am thinking of using either 3, or 5 L brackets made of 2" wide by 1/4" thick hot rolled a36 plate that has been waterjet cut into the specified L shape and size.  The brackets will set "edgewise" against the mounting wall, with bracket tabs welded on at the top, and the bottom of the back to support the load.  The load bearing surface of the shelf will be covered in thin plate, likely 1/8"   Also the 850lb load will be evenly distributed across the shelf, however the load is only 18 inches wide (deep).  In order for it to fit on the bracket, the bottom leg will need to be 20.5" to account for the dimension of the rear brace.   The reality in that case is, that the center mass will be shifted 2" away from the wall mounting plane.  

The shelf will be 48" (long) against the wall.  

If I were to use 3 brackets, and 3 top fasteners (one at each bracket) and 3 bottom fasteners, how would one calculate the rotational load of the bracket, and in …
Can anyone tell what is the difference between data analytics and data science?
I am trying to figure out how this equation works but I cannot understand the steps.

Calculate demand with 10% lower rate
50 per hour
% change quantity (Q1 – Q0)/Q0
(Q1 - 2,000 )/2000 = 1- (Q1 /2000)
% change price -10% = (P1 – P0)/P0
Elasticity = -.5 = [(Q1 /2000)-1]/-10%
Solve and get Q1 = 2000 x 1.05 = 2100
Demand goes up 100 hours
P x Q = Revenue = 45x2100=


The steps in this calculation are:

Elasticity = ΔQ% / ΔP%
Elasticity = [(Q1 – Q0)/Q0] / [(P1 – P0)/P0]
Elasticity x [(P1 – P0)/P0] = [(Q1 – Q0)/Q0]
Elasticity x [(P1 – P0)/P0] x Q0 = (Q1 – Q0)
{Elasticity x [(P1 – P0)/P0] x Q0} + Q0= Q1
{-.5 x [-.1] x 2000} + 2000= Q1
{100} + 2000= Q1
2100= Q1

Can someone explain to me the steps needed to solve this?
I cannot seem to arrive at the same answer as the example. Therefore I dont
think I understand the proper order and steps required. Can someone explain so I can improve my skills?

Is there anyone that can help?

he cut some apples into eighths. she and her friends ate all but 17 pieces. how many whole apples and parts of apples did she have left over? tell how you know?

I am doing a fitness trainer course alongside my computing and I am confused about the terms used to rotate the hip. The images on Google images also seem to be conflicting

Imagine the knee is bent and lifted up I thought lateral rotation was moving the hip away from the midline of the body to the leg makes a 'r' shape with the feumr being the top of the r and medially rotation was turning it back to its starting position.

This page states that external rotation is lateral rotation and it is the rotary movement that is occurring in the vertical axis when the femur moves away from midline, thereby turning the thigh or pelvis outward.1 the hip can rotate externally 45 degrees.


I extrpaolate from that that medial roation is internal rotation. Correct?

However the image I have attached called incorrect internal and external extension seems to suggest the opposite of the website. The second image is what I would have expected to see

Is the first image incorrect or have I misunderstood as there are so many different sites and pictures it can get confusing. But the second image is intuitive which does make it feel correct. The first image could be a labeling error. I hope so :)

Many thanks in advance