Wednesday, September 23, 2015

Episode 069: The Physics Quiz - Particles

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First off, Happy Autumnal Equinox! The first day of fall is upon us! At the equator, the length of the day and night is roughly equal, hence the name equi, meaning equal, and nox meaning night.

This week, the podcast episode focuses on an app that I came across a couple of weeks ago, called The Physics Quiz. I really like this app. It contains over 600 questions relating to particle physics created by Dr. P. Nilsson, a scientist stationed at CERN, a particle accelerator facility located in Geneva Switzerland. I reached out to him regarding featuring his app on the show and got his blessing. It was very exciting talking with someone who does research at one of the leading science facilities in the world!

I took the quiz 3 times, and included on the podcast is me on take 3, on the easy setting. It's a fun quiz. On take 3 I scored an 8 out of 10. I'll be posting take 1 and take 2 as bonus Physics Phrydays.

I think apps like this are fantastic. They test your knowledge and keep you interested, and make physics not seem like work. Its something that you can play with friends who aren't even in the physics field. I without warning sprung a quiz on one of my friends while we were out at dinner. It sparked a lot of interesting conversation and we had a good time!

One word of warning: Quiz levels Medium and Hard are rough. I scored a 6/10 on medium and 4/10 on hard. The questions are excellent and help you learn, but you are certainly going to have to earn your score! Another great thing about this app: the price. It's only 99 cents! Well worth the dollar and certainly has earned a permanent place on my iPhone. I find myself coming to it when I have a few minutes of downtime here and there. Who knows, maybe I'll spring it on some future guests of the show!

You can reach out to The Physics Quiz on twitter Here or click the link at the top to check it out for yourself in the app store. Enjoy!

Thursday, September 17, 2015

Physics Phrydays 05: Ten Physics Questions You Should Know as a Physics Graduate!

Physics Phrydays returns! I have been feeling very pop-quizzy the last week or so, so I decided to bring back Physics Phrydays because I found this really cool quiz online, and thought it would be fun to take it live in real time and share it with you. (I got 9/10, not bad!). Check out the quiz HERE if you want to play along.

This episode has a two pronged effect. 1) I am preparing for a very different type of quiz coming up on the next episode of the podcast. To test my strength and knowledge, I thought I'd ease in with a softball quiz and post it for your listening pleasure. It's actually surprising how much of it we've covered so far on the podcast. Allegdly, these are questions you should be able to answer as a Physics graduate, so keep it in mind. If you're a graduate, do you remember all of this stuff?

Second part of the two pronged effect: I am still committed to finishing The Elegant Universe, and so I'm trying to slowly bring back Physics Phrydays, and encourage myself into reading that book. It has again eluded me. But, here we go, slow but measured progress. Enjoy!

Tuesday, September 15, 2015

Episode 068: 7 Question Physics Brush Up Pop Quiz!

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Pop Quiz:

1) What is the derivative of cos(x)?

2) What is the 45 degrees in radians?

3) Remember the cosine of 45 degrees?

4) Can you convert kilometers to miles?

5) Which two sides of a right triangle are used to calculate tangent?

6) Is displacement a vector or a scalar?

7) An object is launched into the air at an angle of 60 degress with respect to the horizontal. What are the velocities in the x and y directions?

--------------------------------------- ANSWER ALERT!!!

So, how did you do??? Here are the answers:

1) What is the derivative of cos(x)?: The answer is -sin(x). We haven't quite covered it here yet, but the derivatives of trig functions are essential for doing well in Physics.

2) What is the 45 degrees in radians?: The answer is pi/4. We can calculate this by multiplying 45 * pi/180 = pi/4.

3) Remember the cosine of 45 degrees?: The answer is sqrt(2)/2. We can remember this by reviewing Episode 24: Sines and Cosines by Counting to 4 episode of the podcast.

4) Can you convert kilometers to miles?: 1km = 0.621mi. If you know that there are roughly 1.6 km in a mile, we can use a conversion factor to solve: 1 km * 1 mi/1.6 km = 0.621mi.

5) Which two sides of a right triangle are used to calculate tangent?: Recalling sohcahtoa, we can use TOA, or tangent = opposite/adjacent to answer this question.

6) Is displacement a vector or a scalar? Displacement is a vector quantity, while distance is a vector, as it does not include a direction.

7) An object is launched into the air at an angle of 60 degress with respect to the horizontal. What are the velocities in the x and y directions?: This is a matter of breaking our velocity vector into components. We're not given a velocity so we can use a generic velocity v. vx = v*cos(60) = v/2 and vy = v*sin(60) = v*sqrt(3)/2.

So how did you do? This is a 7 question quiz. Each question was taken from a single app from the Physics Brush Up app bundle. Calculus. Radians vs. Degrees. Sin vs. Cosine. Unit Conversion. Sohcahtoa. Vectors vs. Scalars. Vector Components. If you were shaky on more than one question, you should consider grabbing it. You'll thank yourself later!

Sunday, September 6, 2015

Episode 067: 7 Killer Physics Brush Up Apps for the Long Weekend!

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Summertime is winding down and it's coming time to get back into the swing. For some of you school has already started. And, if you took the summer off, the rust is probably good and settled in on all of your old critical physics and mathematics knowledge from years past. Break off the rust with these 7 killer apps now on the app store! As a special offer, if you buy all 7 apps, you'll get a ~50% savings! Click below for all the details.

Grab the App Bundle Here

Download The Exploring Physics: Unit Conversion App

Download The Exploring Physics: Radians vs. Deg App

Download The Exploring Physics: Vectors vs. Scalars App

Download The Exploring Mathematics: Sine & Cosine App

Download The pwn mathematics: sohcahtoa App

Download The pwn physics: vector components app

Download The Exploring Mathematics: Calculus Review app

Wednesday, September 2, 2015

Episode 066: Dot Product Example- Work From A Wagon!

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Via Physics Today's Facebook: On this day in 1859 (and on the day before) one of the largest geomagnetic solar storms ever recorded struck Earth. The Aurora Borealis was seen as far south as the Caribbean. Telegraph systems all over Europe and North America failed. In the Pacific Northwest, the aurora was so bright that people could read a newspaper at night by its light. According to calculations by insurers Lloyd's of London and risk assessor AER, if a storm of the same magnitude struck the US now, it would cause up to $2.6 trillion worth of damage. The storm is known as the Carrington event after the British astronomer, Richard Carrington, who recorded the storm's genesis as a sunspot on 28 August.

And...on with the show.

Example: You pull a box of rocks in a wagon across your yard. You grab the handle at a 45 degree angle, and muscle your box of rocks across the yard at a sold 100N of force, constantly, for a distance of 10 meters. What is the total work done on your journey?

We can calculate the work with the following formula:

W = Fd

In Episode 064, we learned the 5 steps for doing any dot product.

1) Identify two vectors- in this step you will need to simply locate the two vectors you’ll be “dotting”.

So far, so good. We know that we need the Force and the displacement, which are given in the problem: F = 100N, and d = 10m.

2) Identify number of dimensions- i.e. [2,0] and [4,3] are both two dimensional, because there are two numbers, or components, inside the brackets, [2,0,5] and [4,3,-9] are 3-dimensional vectors.

.... uh oh. Our force vector and displacement vectors are not given in terms of coordinates, we're simply given their magnitudes. If you recall from the end of Episode 064, I had mentioned that there is a "quick" way to perform the dot product, which was

W = Fd = F*d*cos(theta)

where F and d are not bold, representing the magnitudes of the vectors, and theta being the angle between them.

So, we simply multiply 100N*10m*cos(45) = 1000*sqrt(2)/2 = 707.10 J!

Tuesday, September 1, 2015

Episode 065: 8 Ideas to Effectively and Productively Use Your Textbook.

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The ol' textbook. It's one of those things that seems so obvious and yet can be so easily cast aside. Included this week are 8 HOT tips to use your textbook. Included below is an image version that you can print out and hang above your bed at night. Have fun!

Read It!- I know this may sound like a very simple thing but I can't tell you how many classes I would only use the textbook as a last resort when what I learned in class wasn't enough. Getting into the habit of reading your textbook is a simple, but major step forward.

Read The Night Before Lecture- This is a great way to get a preview of your next class. If your professor is following the textbook closely you will be in great shape the next day. Also a great way to relax before bedtime! Let your subconscious crank on the new information and then use class to reinforce it.

Don't Get Overwhelmed- Sometimes the text is dry, but also filled with a lot of information in a very short amount of text. Take it slow, reread it if necessary, and don't give up. If you even get a piece of it during the read, you will be able to grab the rest during lecture. You'll also know exactly which questions to ask.

Get a Highlighter- Don't highlight the whole book! Use your highlighter wisely and for absolutely delicious information only. It will save you tons of time when trying to find those passages later when you're doing your homework.

Dig for Gold- Sample Problems and Step-By-Steps are gold just waiting to be unearthed. Most of the homework problems are variants or will easily fit into step-by-step procedures.

Look at Your Homework First- Many times your homework will be assigned early. Even if you don't start early, knowing what you have to do is great at being able to pinpoint sections of the textbook that will help you later.

Review what you Read- When you're feeling saturated, take a break and think about what you just read. It will be a good rehash, and force your brain to solidify those memory pathways for good retention!

Start Making Your Cheat Sheet- Do not take copious notes. If you find phenomenal information that you think would save your life on a test, take a sheet that you can put in the book and jot down a very short amount of information. You'll be starting your cheat sheets and making intelligent notes instead of encyclopedias worth of notes.