Revmixman

My professor provoked a conceptual question in which I hope to figure out before next lecture. Basically, I want to know why in Matlab or any other similar programs do processes take a seemingly random amount of time. For example if I run:

tic

total = 0;

for k = 1:999

if(isprime(k))

total = total + k;

end

end

disp(total)

toc

with tic and toc setting the beginning and end of the timer, respectively. Running them for the first time gives:

Elapsed time is 0.480989 seconds.

running it again 5 more times consecutively:

Elapsed time is 0.091201 seconds.

Elapsed time is 0.096824 seconds.

Elapsed time is 0.094463 seconds.

Elapsed time is 0.234582 seconds.

Elapsed time is 0.124880 seconds.

So the first time it ran extremely slow. One student said it's because the process was stored in the RAM. However, the professor shot that answer down. He said the process should take the same amount of time. Then he said to take a look at the 2nd, 3rd, 4th and so on process times. Although they are close, they aren't exactly the same. Why is that? My thoughts are that background processes are all being executed and a truly accurate timer would have no processes at all, except for the Matlab program. What do you think?

This question might be too technical so if you want to just point me to a good source, I'll read more on my own. But if you happen to know, please share. Thanks in advance!

I'm curious for anyone who is old enough to remember what happened when the NFL added a new team. I think the last team added was the Texans in 2002. Did they take players from already existing teams? Did the new team get extra draft picks? Or did they just sign a bunch of free agents and suck for a while as they built their team up?

I'm a college student at UCD in California and the only job I had this year was in Alaska for the summer. I made about $8000 and also took out student loans and received financial aid for the year. My question is, do I put that I was a resident of California or Alaska? And which state would I pay taxes too? Any other useful advice you have from your experiences would also be appreciated.

The other day, I visited a friend at her apartment for a few hours and she told me to find an empty parking spot in the parking lot. I noticed a sign at the entrance that said something like "cars without permit will be towed at owner's expense". Of course, these signs are common and I have learned over the years to simply not park in parking spots that say "reserved" or have some sort of unit number painted in it. I parked in a spot that had absolutely no paint, besides the white lines indicating it was a parking spot--usually these are visitor spots. 3 hours later, my car was towed and I had to pick it up the next day since they closed for the night. Nevertheless, I paid $265 to retrieve my vehicle and I am more than upset. So basically, I would like to know if it is legal practice to tow vehicles from unmarked parking spots. This was in California.

Before you answer, let me give you a bit of background. The speed of sound is proportional to the temperature of the medium it travels through. For air on earth, the speed of sound is 340.27 m/s at 15 deg C and slows all the way to 248.15 m/s near absolute zero. I made a linear plot of the known data and got the equation y = 0.6016x +166.8. y is the speed in m/s and x is temp in K.

If I plug in the speed of light for y, and solve for temperature, the equation says for sound to travel that fast temperature must be 498.3 mega Kelvin.

Theoretically speaking, do you think sound can achieve speeds that high, or even faster than the speed of light, if we could achieve those temperatures?

Also if you can find any articles or previous discussions on this matter, feel free to include the links.

I am trying to understand how transformers work. Right now I know that the amount of turns on the secondary vs the primary is what determines the voltage ratio change. For example if there is a starting voltage of 60 volts going through the primary which has 10 turns and then through the secondary, which has 20 turns. The ratio is 20/10 = 2/1 (a step up) so 60 volts becomes 120 volts.

What I don't understand is, what if the primary has 200 turns and the secondary has 100. Same ratio so same voltage will result. How do you know how many turns to start with? Or said differently, what is the difference between very few turns and very many turns given the same ratio? I hope you understand my question.

My grandma has always been recognized for her good cooking. I grew up around it, so I got used to it. As I got older, I would see her less often, but when I visit she always warms me up something to eat. The problem is her food is often too salty! I would mention it to her a few times but she says her cooking has always been the same.

Now, obviously you can't taste the food for yourself so my question to you is, do you think my grandma is:

a) getting old and her taste buds are failing, so she compensates by adding more salt?

or

b) my moving away caused me to desensitize myself from her cooking and its always been salty?

Maybe let me know if you encountered a similar experience with your grandparents (or maybe you are a grandparent and your children have started complaining too).

I seem to get it every time I eat something dry without taking a drink first. It goes away after I take a drink, but I heard other people get the hiccups for other things. When do YOU get it?

When I start my car it idles just fine but if I turn on the lights, in begins to idle fluctuate. This indicated to me that the current was too low for complete combustion. I thought I may have had a bad battery so I replaced it with a brand new one (the best one from Autozone). The battery was confirmed to be going bad and it seemed to help a little bit but now I noticed another problem. One night I was out driving and I accelerated hard (just for fun). I took my engine to about 7000 RPM when I noticed the headlights dimmed dramatically. It scared me because it looked as if the lights shut off. I took the car home. A few days ago, after pondering what could have caused the lights to dim, I decided to check the voltage display on my ECU controller and drive it again. It states the voltage is about 13.2 V while cruising with the lights on (about 13.5 V with lights off). If I hit the accelerator the voltage remains the same up until about 6000 RPM it begins to drop to around 12.8 V, 6500 RPM it drops to 12.4 V, and about 7000 RPM it starts fluctuating different numbers around between 10-11.9 V.

This is not good. I initially thought my alternator might be bad, but an alternator shouldn't it generate more current at high RPM?

The car is a well taken care of 1993 Honda Civic Ex.

Other things I have changed are my cap and rotor, spark plugs and wires.

Any ideas? BTW I hope for more than just a "try this" or "replace that". I need to understand how you came up with that conclusion, if possible. Thanks.

First of all I live and work in California. I work at a gas station approximately 9.5 hours a day, 8 hours alone. According to the Wage Order my employer is required to allow me two ten minute breaks (restroom breaks not included). But, due to the nature of our business, this is unable to be satisfied. The store averages about one customer every minute. A ten minute break would require a sign stating to wait ten minutes every four hours. This simply is not feasible to do comfortably. I say this because I work in a kiosk and if a customer approaches the window and sees me sitting down doing nothing (taking a break) they knock on the window for me to service them. I can either tell them to wait ten minutes while I finish my break, and I can assure you they will uncomfortably stare at me every second of that break (in addition to a growing line behind them), or I can succumb to their wishes and give them service. Just to give you an idea of how uncomfortable it can be, I work in the ghetto where the population is primarily minorities who have no problem raising their voice to get what they want.

My station is one of many owned by a corporation in Southern California. This corporation has weekly memo's in the form of a video, that remind us of new policies, rules, etc. One such memo was in regards to our breaks. In the video we were told that if a ten minute break is unable to be taken, to instead take a 2 minute, break. Then later, take a 3 minute break, then later take another 2 minute break, and so on. As I said earlier, we average 1 customer every minute. So in my case I would often take my break in even SMALLER portions. It got to the point where my breaks are so small it doesn't really feel like a break at all! At the end of the day I am left feeling exhausted and demoralized, yet I continue to return to work because I need the money. But I am finally fed up. I have begun to ask myself if this practice is even legal?

So I did some research and according to the DLSE Manual, a rest period is defined as a full ten minute break without any work related activity in between. A succession of several small breaks taken throughout the day does not meet the rest period requirement in the Wage Order. And if a break is not give, an hour of additional pay should be given for each day.

I have been employed here for about 3 years; back pay for missed breaks would total over $7500. Do I have something here or am I overreacting? Maybe I am the first to complain because I don’t take smoke breaks like the others. But regardless, I am just hoping someone can provide me with some insight before I make a fool of myself (and risk my job) requesting back pay for missed breaks.

First of all I live and work in California. I am scheduled to work at a gas station for 9.5 hours, 5 days a week. 8 hours of the day I am working alone, which limits my ability to take a 30 minute lunch break. As a result, my employer had me sign an on-duty meal period waiver form when I got hired with the company.

Here is a quote from the DOL. "Unless the employee is relieved of all duty during his or her thirty minute meal period, the meal period shall be considered an "on duty" meal period that is counted as hours worked which must be compensated at the employee's regular rate of pay."

So, my question is, how is this calculated into my paycheck? It seems as if I should be receiving additional hours on my paycheck. But, after reviewing my time sheet and pay stub, this does not seem to be the case.

For example, between August 13th - 19th I was clocked in a total of 52.75 hours. I get paid weekly. On my paycheck under earnings it is calculated as HOURLY RATE ($10.00) times HRS (40.00) equaling an AMT of $400.00. The next line says OT RATE ($15.00) times HRS (12.75) equaling an AMT of $191.25. The total simply says 52.75 HRS and $591.25.

Is my company robbing me? Where is my on duty pay? I haven't even mentioned that I do not receive 10 minute breaks, but that is for another post.

Last night I was driving to work (graveyard shift) and there was construction being done on the freeway. As a result, there were some cones restricting the freeway to just one lane. A Mercedes SUV was exiting the same exit as I was taking. At this point the cones open up to allow us to exit. As we approach the downhill off ramp, the SUV seems to be confused and begins to break. I brake too but I assume he is just slowing down for the off ramp so my braking isn't as hard and I let our distance close in. He stops. I realize this and try to avoid him by applying more pressure but the combination of gravel from construction and downhill causes me to skid at about 5 mph and I hit his rear bumper, with my headlight apparently. I have minor damage, notably a broken corner light which will cost me about $250 and a small scuff on the headlight. He has a light scuff on his bumper. He tells me we don't have to exchange information because the damage is unnoticeable but I suggest we at least exchange numbers... just in case. I received a text the next day saying how he will take his car to the body shop next week and "let me know". My question is, neither of us has admitted fault. I assume I am going to be even though he made a complete stop on a freeway off ramp for no reason. He said he was confused and did not see me behind him. Should I prepare to notify my insurance? No police were involved. Also who is at fault?

So I saw someone post this on youtube while watching video on the Japanese tsunami and I was curious how such a creepy coincidence could occur?

"On 9/11/01 many Americans were killed.

On 3/10/11 many Japanese were killed.

Add them up and you get...12/21/12", which is supposedly a day where an even greater amount of people will die. Now, I don't believe in any of this crap. I was just wondering why coincidences like this keep happening to give more credibility to the conspiracy theorists?

So if class starts at 8:00 and gets out at 2:30, what do the school bus drivers do in between that time. And do they get paid for it?

I sometimes race at the track and I have a problem with my windshield wipers flying up at high speeds. My first impulse was simply to remove them, but I recently got a vehicle citation by the highway patrol for not having them. I am just curious if any racers (or fast drivers) have had this problem with their windshield wipes flying up when driving fast and what was done, if anything, to fix it.

It obviously has something to do with wind drag.

My friend listens to Pandora daily from his iPhone and Mac. He claims he was given an exclusive radio station that plays only music of his interest, but the songs can't be thumbed up or down. Supposedly he rates every song up or down and after months of doing this, Pandora figured out what he likes and made him this exclusive station. I checked the station out for myself and it is in fact true that the songs can't be rated. I am basically looking for a hardcore Pandora user to tell me if they had a similar experience.