Davy

I've got a semi-unique situation here with TI 84 programming.

Part of a program I'm working on need to reference a string that is user created, but often the program needs to be run based on the same string input, and the strings can take a little while to type in. So I want to instigate a feature that displays the string variable before the input step and asks if the user wants to use it, or enter a new one.

However, this process only works after the program has been run before. If it tries to display a null string, the calculator throws an undefined error.

I ran into a similar problem when doing something similar with a matrix. I learned that you can use the Dim command to set dimensions to a null matrix and it fills in with zeroes, so that you can make set the matrix to the expected size and compare against zeroes. Is there a way to do this with strings? Like to define it if it's undefined, but to not change its value if it is defined?

If not, is there a suitable work around that would prevent the user from getting undefined errors?

If not, I can always just put in a line that asks if there's a stored value to use, then it's the users own fault if they say yes when it's undefined, but I'd like to minimize errors wherever possible.

Thanks in advance!

The TI-89 has the commands dealing with trying and catching errors, as outlined on http://tibasicdev.wikidot.com/68k:try . What I'm wondering is this: If I write a program on an 89 that uses the try command, and then put the program on an 84, will the 84 still be able to interpret and execute if there's an error in the try block?

Thanks!

You want to wind a solenoid .0245m in diameter and .16m long, in which the magnetic field will be .025T when a current of 3A flows through it. What total length wire do you need?

I'm not sure where to go with this problem. I think that I'm supposed to solve for the number of loops required to generate a field .025T with 3A of current, and then use the diameter, final length, and turns to get total length, but I'm having trouble figuring out which equation I can manipulate to get that.

So could I get a little help getting started please?

http://www.webassign.net/sercp/p16-40.gif

Find the equivalent capacitance between points a and be for the group of capacitors connected as shown in the diagram above. C1 = 5mF(microfarads), C2 = 10 mF, and C3 = 2mF.

I know that you break down the lower two C2 into one 20mF capacitor using parallel capacitor rules, but those only apply if the left and right plates have the same potential between capacitors; I can't justify combining the left or right sides of the top box because that C3 capacitor messes things up.

So could someone point me in the right direction of what to combine in the top portion?

Thanks!

I got my wisdom teeth out today and a little while ago I was laying down icing my face when the doorbell rang. I went to the door and found, from left to right, a bag of goldfish crackers, a bag of Swedish fish, and a bag with a real live fish (not sure what kind, but a small one in a Walmart bag) outside the door. Whoever it was was sneaky enough to escape through the desert behind my house, and the pain meds haven't left me feeling too great as to chase them. I picked them up and found a card that said "evelution" and on the back spelled correctly, "evolution!" in a slightly different handwriting.

So, is this little fish evolution trio supposed to be a well known meme, an important reference, an obvious appeal, or a gift associated with wisdom teeth? Whatever it is, I really don't get it, so if you (anyone) knows why, I'd appreciate an answer.

I'm having trouble seeing where all the values come from in this problem.

Two packing crates with masses m1 10.0 kg and m2 5.00 kg are connected by a light string that passes over a frictionless pulley as in the figure. The m2 crate lies on a smooth incline of 40.0°. Find the acceleration and tension in the string.

Image:

http://www.webassign.net/sf5/p4_20.gif

So I drew the free body diagram, Tension up and mg down on m1, and on the second mg down, normal force perpendicular to the incline, and a force pulling up the incline. I think that the acceleration times the mass of the object on the ramp (m2a) will equal the tension, but I'm not sure why, and I also don't know what to call the force pulling up-left on the 2nd fbdiagram (is it equal to m1g?) .

Logically I assume I want a system of 2 equations with variables T and a to solve for, but I'm just unsure as to where to pull the numbers from, and I need to understand why not what if I am to do well on the upcoming test.

So, help me please?

I'm looking at ordering tickets for 'Can't stop the serenity' at Tucson fox theaters. The tickets have to be bought online then picked up prior to the showing. There's a discount for students, and I want to make sure I'm doing it correctly.

Do I just order it as a student ticket and then present my high school ID when I pick up the ticket, or is there something more/different I need to do?

I know you can set the rand function, for example 0 --> Rand instigates the default (Zero) seed, and any other number generates a different seed. Is there a way to check which seed the calculator is using, though?

For example if someone put in a random number for their seed, and you noticed that during a RandInt(1,100) it picked 37 six times in a row and you wanted to recreate that but they didn't remember what seed they had set it to, can you make the calculator return the RAND seed's number?

hau du ai shawt vep

I was getting this error message for a couple days when trying to reply to a certain email that was a reply of reply going back a ways, so it was really big. Every time I tried to send my reply I got a temporary error 2 message. It would lock up all sending and saving of drafts, even for new, unrelated messages. Can you get Temporary Error 2 from the Email just being too long?

Hey,

so a few years ago I got a free version of VS 08 on my computer and used it to compile a simple C++ program and it worked fine. The deal with this version is that it is not registered, so I don't have access to the core program but I can use the "Visual Studio 2008 Command Prompt". I would write it in a text file then use the compiler to make it into an .exe (actually it saved as both an object file and an .exe). Now I'm trying to do that again and I can't remember how. I'm pretty sure what I'm supposed to do is open up the VS command prompt, find the correct directory, then type in :

(command here) program.c

but I can't remember for the life of me what that command is. Help?

Hello! I have 2 questions about mirage OS.

The first time I used it, after I did the :: thing and it appeared in mirage OS, the program disappeared from my programs list and I could no longer edit it. I did this to other programs and they didn't disappear. Any idea what caused this?

Also, If I have a program that accesses several others, do I only need the core program in mirage OS and can the others be archived and still be able to run?

The first question is the more pressing matter, I'll probably find out the answer to the second after some more playing around with it.

My teacher said that it can act as both and we are supposed to find out how we can make it act like either. I've been searching around and I keep on finding things that say it CANNOT be a base. Can anyone clear this up? I've found a few things that say it is Amphoteric, but it never tells why it has basic properties. can anyone explain this to me?

I've got 2 questions here if anyone can help:

Consider the following reaction:

P4(g) + 5O2(g) <==> P4O10(s)

If the initial concentration of O2(g) is 1.0 M, and "x" is the equilibrium concentration of O2(g), what is the correct equilibrium relation?

I know the answer is

Kc = 5/x6

but I don't know how to get there.

Also

Consider the following reaction:

H2(g) + I2(g) <==> 2HI(g)

If the value of Kc for this reaction is 25 at 1100 K, and initially only 4.00 M HI(g) is present, what is the equilibrium concentration of I2(g)?

0.571 M

Same deal with answer

Help?

7. Given:

2A(g) + B(g) --> C(g) + D(g)

When [A] = [B] = 0.10 M, the rate is 2.0 M*s-1; for [A] = [B] = 0.20 M, the rate is 8.0 M*s-1; and for [A] = 0.10 M, [B] = 0.20 M, the rate is 2.0 M*s-1. The order of the reaction is :

I know that the answer will be 2, but I don't know how to get there. Help?

The vapor pressures of pure carbon disulfide and carbon tetrachloride are 360 and 99.8 Torr, respectively, at 296 K. What is the vapor pressure of a solution containing 50.0 g of each compound?

I know the answer is 274 torr, but how do I get there?

i calculated .65 mols CS2 and .3251 mols CCl4, added those two together and got the mole fractions ( CS2 is .63408 and CCl4 is .3659), I multiplied those by their vapor pressures and added them up, and came out with 195. Where is my error?

Hello! I'm working on a review thing for a chemistry test and I'm a little stuck. Here's the question:

The gauge pressure of an automobile tire is typically 32 to 34 lb in^-2. Which of the following pressures corresponds most closely to this pressure range?

A) 1500 kPa

B) 1500 Torr

C) 230 kPa

D) 1500 mmHg

E) 45,000 Pa

I know that C is right, I just have no idea how to get there. Mainly, I just don't really get what In^-2 relates to (It is a superscript in my assignment, YA doesn't like superscripts).

I'm trying to find any pokemon with a special attack of 176 so that I can catch a charmander, but it seems everything I do ends up being 177 or 178, it never hits.

For those who don't understand what I'm talking about, it's that you can catch any pokemon in the game by using the same thing as the way to get mew (Flying away from the gambler as he sees you, get in another trainer fight to unlock your keypad, and fighting a ditto when you have a pokemon with a special attack number that is equal to the decimal of the hex form labling the pokemon, I've used it to catch every pokemon besides charmander and kengaskahn, since kengaskahn's hex decimal equivilent is 2 and charmander is 176, I can't get either with ease.)

So yeah where can I find a list like that, or do you just happen to know at what level which pokemon in pokemon red (the old one) has a special of 176?

I understand that it's because of the poison in the bite, but what my question is is that what is getting bigger in there? Does Puss build up, or is it something like fills the area to dilute the poison? Thanks!

I hit the "New Program" Button, curious about what I could do with it, and now I can't delete my blank program. Can anyone help?