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Hi people ! ( Sorry if my english isn't good )

 

I need help for a transcript, because i'm unable to understand anything :

 

http://vocaroo.com/i/s0J3zBhsVgmV

 

i tried to make something but .. yeah :

 

... eleven o'clock in the morning , ... weekdays you now, they are like two black usually there are just one black person or maybe two and there is like one chick, she's like «  oh  you know .............. »  .... Barbra Walters is on the show

If someone could help me , that would be really great :)

 

It's coming from this video :

Edited by Elodith

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Anyone here good with logical fallacies? This isn't exactly for homework, just for a personal project that I hope to be done with in the next month or two. Examples of things I need help with:

 

Is "correlation does not imply causation" a formal or informal fallacy? I read that it's informal, but I also read that it's a type of "affirming the consequent", which is formal.

 

Similarly, is the "fallacy of anecdotal evidence" formal or informal? I read that it was formal, but it's a type of "cherry-picking", which is informal.

 

I'm also having a tough time figuring out what fallacies are types of "red herrings", not to mention fallacy origins in general.

 

Even if you don't know the answers, if you're willing to discuss them with me in hopes of figuring them out, I'd appreciate it.  :kindness:

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PHYSICS HELP PLS

 

Okay so like idk what im doing in physics.  I'm really stuck on one problem which has a bunch of questions it asks about said problem:

 

A car going 110. km/h sourthwest reaches a curve in the road. Assume the curve is an arc of a circle. After rounding the curve, the car's velocity is 110. km/h west. The car takes 2.50 s to round the curve.

 

It asks 13 questions, 

 What is the initial/final velocity of the car in E-W direction?   initial/final in N/S direction?

change in velocity in E-W? N-S?  

magnitude of total velocity difference?  

direction of total velocity difference (express in True North angle) 

magnitude of acceleration, direction of acceleration (True North angle)

length of car's path (in meters)

How long would the car take to travel the same distance if its speed were 100 km/hr instead of 110 km/hr? (in seconds)

 

 

That's a lot of questions but if any of you guys are good at physics im sure this is easy stuff for you. Any help on how to work these is super appreciated and needed D:

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@

Okay, assuming the deadline has yet to pass, here's what to do. We're heavily using vectors and trigonometry for this.

I think that "southwest" implies a 45 degree angle. In the east-west direction, east is positive (+x direction on cartesian plane). For north-south, north is positive (+y direction). The speed of the car is the same at the beginning and the end, though the direction changes.

So: initially, the car is going 45 degrees southwest; in E-W, this is -(110kph)*cos(45) (negative because it's going west), and in N-S, -110kph*sin(45). The final velocity is straight west; this means -110kph E-W, 0kph N-S.

The change in the velocity, for each direction, is final minus initial velocities. Be careful to use the right signs.

The velocity difference, the vector "delta v", is just a vector with the components of the differences. Its magnitude is sqrt((delta vew)^2 + (delta vns)^2), where delta vew is the difference in E-W velocities and delta vns is difference in N-S ones.

Direction, we use trigonometry. The reference angle is tan(delta vns/delta vew), which becomes easier to see if you draw a right triangle. The delta v vector is the hypotenuse, the N-S and E-W components the legs of the triangle, and the angle is between the hypotenuse and the E-W leg. Then, find the angle between the vector (hypotenuse) and the north direction, using the angle you found and the fact that there are 90 degrees between N, E, S, and W.

The (average) acceleration vector is simply delta v over delta t, or your previous vector divided by 2.5 seconds. This means that its direction is the same as the delta v vector, and its magnitude (and each of its components) are just divided by 2.5 seconds. You may want to convert delta v to meters per second, or you'll end up with the odd unit "kilometers per hour per second", which is not very useful.

The path length may seem complicated to figure out until we realize that the car never changed speed, just direction. Therefore, it was traveling at 110 kph the whole time, and took 2.5 seconds to cover the path, so the path must be of length (110kph)*(some conversion factor, go to meters or kilometers per second)*(2.5 seconds). If the car were going at 100 kph instead of 110 kph, it would still have to cover the same distance. So using v= d/t, solve for the new t using given v (100 kph) and known d (from previous part).

Hope that helps, let me know if anything's unclear!


@@Blique, I would call these informal fallacies. Anecdotal evidence is only wrong because it's inductive reasoning; what really makes it difficult is that our minds are biased to give them undue weight. Correlation not implying causation is more about the reasons behind measurements; if you're measuring things, you're already resorting to evidence (inductive reasoning) rather than proof (deductive reasoning, from previous axioms or proven theorems). So either they're informal, or they're not really logical to begin with.

Maybe not the answers a scientist or a logician would give you, but there's my two cents.

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Direction, we use trigonometry. The reference angle is tan(delta vns/delta vew), which becomes easier to see if you draw a right triangle. The delta v vector is the hypotenuse, the N-S and E-W components the legs of the triangle, and the angle is between the hypotenuse and the E-W leg. Then, find the angle between the vector (hypotenuse) and the north direction, using the angle you found and the fact that there are 90 degrees between N, E, S, and W.

I had already drawn out a graph of what i was getting from before, but I'm a bit confused as to where the 45* goes in the triangle.  

TL8kISG.png < kind of redrew it on paint.  Where do I place angles "between hypotenuse and EW" and "hypotenuse and N" 

 

And to check I got EW change in velocity -32.22 and NS 77.78

using the formula for velocity difference I got 70.74

Thank you so much for explaining this to me, I'd never have gotten this far without your help

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@, no problem.

The delta v vector is going to point up (north) and to the left (west). The angle from the tangent is going to be the one sandwiched between the vector and the W direction. The angle you're asked for (from True North, by which I assume they mean a heading angle) is between the vector and the N direction. Since heading goes clockwise, this is a negative angle (or you can add 360 degrees to your negative angle, to make a positive one).

Those numbers look believable. I won't solve the math for you - that's your job - but that sounds about right.

Let me know if you have any more questions! And good luck!

 

EDIT: the 45 degrees goes between your diagonal line and the W direction. (Or the S direction, since 90 - 45 = 45).

Edited by Suukorak

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I need help with homework, but not in any standard ways.

 

You see, in my marketing class in high school, I am currently on a project to create a fake menu for a fictional restaurant.

 

What I need are ideas for 10 La Carte items, 2 Du Jour items, Appetizers, drinks, desserts, and kids menu as well as appropriate pricing.

 

If you can/want to help, let me know and I'll PM you. I'm pretty sure this is due this friday, and I only have a title, type of restaurant, and 1 La Carte item!

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When I need any kind of homework help, I address to the guys from writingcheap.com . They help me prepare any kind of essays or research works etc. Gals and guys, do you use any third-party help like me?

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im good with all sorts of math and some history and science. my english is alright. so PM me if u want help :)

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I'll do my best to help you with just about anything you need, especially mathematics.

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This is a great topic idea. 

 

This is where I can help out. 

 

Creative Writing

Literature

Communications

Sociology

Psychology (Behavioral, anomalistic, evolutionary, developmental)

Chemistry I-II

O Chem

Anatomy and Physiology

Neurology

Physics I-II

Biology

Molecular Biology

Trig

Calculus I-III

Paleo/US/Mexican/European/Asian History

Thesis Research guidance

Religious Studies 

Edited by Just Jessi

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Can anybody help me with a few questions of my Mechanical Engineering homework?

Task 1 

Use logrithmic differentiation to find 

dy/dx for y = e^4x sin2x / (x +1)^2 

 

Task 3

find dy/dx when y = 5tan^-1 (4x^2) 

 

Task 4

find dy/dx when y = tanh^-1 (2x^3)

 

I'm in desperate strait. Is there anybody competent or should I just use the special service like assignment.essayshark.com and not to be annoying?

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You take the natural log of y, then differentiate that d ln(y)/dx. I was going to do it but your notation for the first problem looks wrong. Is e^4x supposed to be e^(4x) ? And what are the arguments for the trig functions?

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Can always help out in English and grammar.

If an alarm starts ringing and flashing, so you say "the alarm went off" or "the alarm went on". Sounds to me that the alarm is on.

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If an alarm starts ringing and flashing, so you say "the alarm went off" or "the alarm went on". Sounds to me that the alarm is on.

Technically it should be "off" because "off" in this context means started sounding. The alarm, if it has batteries in, is technically on most of the time. Hope that helps

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If an alarm starts ringing and flashing, so you say "the alarm went off" or "the alarm went on". Sounds to me that the alarm is on.

 

'went off' is the past tense of the verb 'to go off' which doesn't  mean the same as turning off, it can refer to sounds, explosions or even the decomposition of food, "the alarm went off so we evacuated", "the bomb went off before it could be deactivated" and "I forgot to put the milk in the fridge so it went off". The key difference is the word before off, turning off means to shut down the power but going off refers to the examples I listed.

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If an alarm starts ringing and flashing, so you say "the alarm went off" or "the alarm went on". Sounds to me that the alarm is on.

I agree with @Flugelhorn. In this sense, "To go off" is related to the expression "to set off", meaning "to start" or "to be started". It implies that the subject (The alarm) was in a state of rest, then moved "off" from that state into action.

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I agree with @Flugelhorn. In this sense, "To go off" is related to the expression "to set off", meaning "to start" or "to be started". It implies that the subject (The alarm) was in a state of rest, then moved "off" from that state into action.

The words do not match your explanation. "Go off" might be one of those statements that does not equal the words used. At work someone said "the light went off" when in fact it went on. We should not continue to use words incorrectly.

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The words do not match your explanation. "Go off" might be one of those statements that does not equal the words used. At work someone said "the light went off" when in fact it went on. We should not continue to use words incorrectly.

Yeah, you're right. But then how would one explain the reason for "The alarm went off" being the correct statement?

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Yeah, you're right. But then how would one explain the reason for "The alarm went off" being the correct statement?

I'm saying it is incorrect, and people still say it.

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I'm saying it is incorrect, and people still say it.

So then what would the correct statement be? "The alarm went on"?

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So then what would the correct statement be? "The alarm went on"?

I think so. It sounds more logical.

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