Lv 2322 points

# Hale2bopp

• ### Why does my laptop keep losing WiFi connectivity?

My laptop, a Dell Insprion, keeps losing WiFi connectivity, and keeps showing the WiFi connection as 'limited'. WiFi on other devices like my iPhone works fine, while the laptop has problems. I looked at the power settings too, as it is sometimes set to switch off WiFi to conserve power, but it does it even when plugged in.

2 AnswersLaptops & Notebooks7 years ago
• ### Naïve Bayes Classifier - Machine Learning?

My problem is to classify a set of documents with the help of a Naive Bayes classifier. My question is related to the definition of the probability of the document belonging to a certain topic, given that it contains a set of words.

X = set of words (words which can be used for classification) that a document contains Xi = event that a document contains a particular word C = set of classes to which the document can belong Ci = the ith class to which the document could belong P(Ci|X) is proportional to argmax ( P(Ci) * product of probabilities( P(Xi|Ci) ) )

Suppose the document is about history, and my set of words which pertain to the topic 'history' contains the words {'history','historic','past','event','decade,'year','period','century'} . And suppose the document consists of the sentence 'The history of the Chalos dates back to the 18th century when many an event forced them to give up their historic past and move on.'

The file contains many of the words, but only one occurrence of each. Since we are multiplying probabilities, won't it become a product of many ones = 1? So even though it has many of the words, it still shows the same probability as if it had only one of the words. How can one justify this multiplication rather than an addition in this case?

• ### Need advice on BITS campuses?

So I have just passed out of class twelve and have given all my entrances. I would like to know about the Birla Institute of Science and Technology (BITS) Goa campus as it is my preferred choice.

How is the campus? Are the teachers good? Is it a good college to go to keeping in mind going for further studies in engineering? How is the campus for girls? (eg. hostels, strictness for girls etc.)? And, with a score of 329, am I likely to get a seat in Electrical Engineering or any other good branch in Goa (or Pilani, or Hyderabad)?

I would very much appreciate some opinions or information about the same.

1 AnswerOther - Education8 years ago
• ### My phone is locked and the security code won't work!?

I changed the default code 12345 to another one and I tried locking and unlocking the keypad. The first time it asked me for the code to unlock it, the code worked without any problems, but after that it just keeps saying 'code error'. I am reasonably sure that I remember the code correctly especially since it worked the first time.

Still, knowing that I used 5s and 0s for the codes, I made a list of all possible combinations of 5s and 0s for five digit numbers (32) and 6 digit numbers (64) and tried them all in succession. This didn't work either.

The phone is well and truly locked, I can only receive a call but can't make one, can't even switch it off. What should I do? Should I call my service provider?

6 AnswersCell Phones & Plans9 years ago
• ### Lyrics to a song "I don't know where I'm going but I like the direction"?

I don't know the song and this is a part of the lyrics to the song. Which song is this ?

• ### Question about elasticity of demand curves.?

Elasticity of demand curves at a point on one curve can be found by the geometrical formula

e = lower segment/upper segment

Where the point divides the upper segment from the lower segment. This would mean that elasticity of the curve changes on one straight line demand curve as we go from top to the bottom along the curve.

Also, steeper curves are said to be less elastic whereas flatter curves more elastic.

How do we relate the geometrical formula to compare the elasticity of two different curves? As the elasticity of each curve would change as we go from the top of the curve to the bottom, mathematically how can we compare the elasticity of two curves, since the elasticity of both curves would change?

• ### Does flipping hyperbolae give an ellipse?

Is there a way to flip the individual halves of a hyperbola on themselves? What sort of figure does it give? Is there a way to mathematically find this out?

Help appreciated.

Thanks

I added timeline onto my facebook page just to see how it would look like and, not liking it, removed it from my profile. Now, when I logged into my profile recently it had the timeline format again without me doing anything. And it doesn't even allow me to remove it. Has this happened to anyone? What should I do?

• ### Question about Young's double slit experiment?

If the phase difference between the two sources of light in Young's double slit experiment is pi radian, will the central fringe be dark or bright?

The answer according to the book is dark.

But I don't understand why the difference in phase difference should change the position of maximas and minimans because in the derivation for positions of maximas and minimas, we took a variable phase difference phi and said that if phi is 2n pi, we get constuctive interference. Putting path difference = lambda*phi/(2pi), we get the path difference for constructive interference as n*lambda, where lambda is the wavelength of light.

• ### Question about transistors as a switch?

While using transistors as a switch, we need to jump somehow from the cutoff region of output voltage (high output) to saturated region (low output) and we can achieve this by supplying low input (for high output) and high input (for low output) through the transistor setup.

My question is since we are already supplying low or high input, why can't we just directly use the input as output instead of using this transistor at all? If we need to supply low input to get high output and vice versa, why not just directly use our input ?

• ### Around how much energy does the brain use up while thinking?

Is there any quantitative measure of the amount of energy that the brain uses up while thinking, as opposed to when performing normal everyday tasks which don't require much thought? For example, if I study for three hours, I am normally very hungry, something I wouldn't be if i was watching TV or reading a light book. That, I assume, has something to do with extra brain activity.

• ### Dead pixels on phone.. they move around?

I dropped my phone from a distance of about 3 feet in my sleep about two weeks ago... it had fallen on the screen. When i woke up and picked it up, it had fat black areas in the form of strips. While the phone functions normally otherwise, the black areas have started to shift their shape somewhat and there is also a yellow sort of discolouration around the black area. What worries me is the shape shifting quality of the black area. What should I do?

1 AnswerMobile Phones & Plans9 years ago
• ### Question about conservation of linear momentum during a projectile motion.?

Suppose there is a guy who is carrying a heavy weight with him. He enters a canon and is shot from the canon, holding that heavy mass. Now he undergoes projectile motion. During his flight, he drops the heavy mass. Will there be a change in the horizontal range that he covers?

I am confused because during projectile motion, there is no force acting on the body in the horizontal direction. This must mean that momentum in the horizontal direction is conserved. This means that when he drops the mass, his horizontal velocity should increase and hence he should go faster in the horizontal direction. This means that his horizontal range should increase. But this is very counter intuitive. Am I right concluding that his horizontal range will increase?

Thanks

• ### Question about wave interference derivation.?

In the derivation of the positions of constructive and destructive interference of waves,

y1=A1sin(wt-kx)

y2=A2sin(wt-kx+ ϕ)

and y=y1+y2.

So, y=Asin(wt-kx)+Bsin(wt-kx+ ϕ)

y=A sin (wt-kx)+Bsin(wt-kx)cos ϕ + Bcos(wt-kx)sin ϕ

y=sin(kx-wt) (A+Bcos ϕ) + Bsin ϕcos(wt-kx)

Let Ar cos y=A+Bcos ϕ

And let Ar sin y= Bsin ϕ

y=sin(wt-kx)(Ar cos y) + Ar sin y cos(wt-kx)

y=Ar sin (wt-kx+y)

.

Now, we assume A+Bcos ϕ=Ar cos ϕ , because this is convenient , using the graph where we take two vectors, A along the X axis and B at an angle ϕ to the X axis.

So, Ax = A + Bcos ϕ,

Ay = Bsin ϕ

But, how can we just assume that Ar sin y = B sin ϕ, when we have already assumed that

Ar cos y = A+B cos ϕ ?

According to this, we should have

Ar cos y = A+B cos ϕ [assumed]

Ar = (A+B cos ϕ)/ cos y

Ar sin y = [( A+B cos ϕ)* sin y]/cosy

Ar sin y = (A+Bcos ϕ) tan y

Then how can we assume that Ar sin y = B sin ϕ ?

• ### Question about wave equation and equation for simple harmonic motion.?

In the wave equation, y=A sin (wt-kx). So, y is a function of x and t. y=f(x,y)

In the equation for displacement in simple harmonic motion, y=Asin(wt+ ϕ), so isn't y in this case a function of only time? i.e. y=f(t) ?

But particles in a wave show oscillation about their mean points, which means that they show displacement with respect to time. In that case, am I wrong that y is a function of only time in the SHM equation, and if i'm not wrong, then why is it a function of only time?

Thank you.

A=amplitude, ϕ=phase constant, t=time, w=angular frequency.

Physics10 years ago
• ### Question about calculus... in derivation ?

If y =Asin(wt), then dy/dt=-Awcos(wt). I know why the sin becomes minus cos, but why does the w come out of the sin bracket to become a part of the main equation? Can someone solve this equation and take me through the procedure? Thanks.

• ### Question about airplane stalling while flying upside down?

Since a wing stalls at high angles of attack, how is it possible for an airplane to perform a loop or similar maneuver without stalling?

• ### Why are some gases coloured and others colourless?

What is the property of gases like chlorine gas and nitrogen dioxide, iodine as etc. that they have a certain colour as opposed to most gases which are colourless? does it have something to do with the excited state of the electron on absorption of light? Or with splitting of d orbitals(Like transition metals)?

• ### Quelle est la différence entre pronoms relatifs simples et pronoms relatifs composés?

Pronoms relatifs simples-qui, que, dont , où.

Pronoms relatifs composés-lequel, laquelle, auquel etc.

Je ne comprend pas la différence entre les deux.

Où devons-nous utiliser quoi?

S'il vous plaît, aidez-moi!

• ### Can anyone translate this song from French to English?

The song is "Je Suis Jalouse" by Emily Loizeau. I found it very catchy. And please, no literal translations ! They don't make any sense. I've already tried translating it online, and it makes no sense whatsoever. Here's the song:

J'ai pleuré pendant des heures

Sur ta boite de petits beurres

Celle qui contenait les lettres

Les photos de New Hampshire

Ton voyage en amoureux

Je trouve son nom ridicule

On dirait une marque de pull

Elle voudrait me rencontrer

Nous avoir pour déjeuner

Son mec aussi est géner

Tu dis ça pour me rassurer

Oh oui je suis jalouse

Oui c'est ça tout simplement jalouse

Je suis jalouse

Je mange toute seule au chinois

C'est pratique c'est juste en bas

J't'ai laissé y aller tout seul

Et finallement j'assume pas

Il est bientôt 13h30

Tu t'empiffres comme un chancre

[ Find more Lyrics on www.mp3lyrics.org/FeIu ]

Elle te tenait par le ventre

Moi je rumine et ça fermente

La bile et le glutamax

Se chamaillent dans ma rate

Je me dis ça à chaque fois

Je ne mangerais plus chinois

Oh oui je suis jalouse

Oui c'est ça tout simplement jalouse

Je suis jalouse

Ton Adèle t'a dit ce soir

Qu'elle voudrait bien te revoir

Te parler de temps en temps

Sourions, serrons les dents

C'est vrai c'est assez normal

J'n'y vois pas d'inconvenient

Je n'vais pas faire un scandale

Pour vous deux c'est important

mais c'est l'art de ma jalousie

De ne pas savoir te dire

Oui ca me fai un peu bizare

Que vous vouliez vous revoir

Et oui je suis jalouse

Oui c'est ca tout simplement jalouse

Oh oui je suis jalouse

Oui c'est ca tout simplement jalouse

Je suis jalouse