pwn your hw | physics / math / calculus / science / homework preparation and review- eli hibit Learn about or get an edge on your introductory physics course with this podcast!

December 21, 2015  

The one where your host finds goes through another volume of reviewing.

Check out the blog at pwnyourhw.blogspot.com for more! 

And if you're so inclined, grab an app or two or three here: https://itunes.apple.com/us/developer/elijah-hibit/id578486296

Oh, and the Facebook page now too: Facebook.com/pwnphysics

Give us a like, it would really help!

In this episode, we're pushing towards final time, and also towards episode 100, so we're taking stock of where we've been, where we are, and where we're going. For midterms and finals, it's so important to make sure the basics are under control, so here we roll through a little 3 question quiz for the following topics: Linear Equations, Calculus, Kinematix, Force. If you don't have the questions asked in this episode locked down please, please do yourself a favor and grab the apps or the bundle. This stuff is so important to know absolutely cold for your big exam!

Lines & Linear Equations: 
Many physical systems follow linear and parabolic relationships 
What properly of a linear system controls the steepness of the line?? 
What is the highest order in a parabolic equation??

Calculus 
If you’re in physics, prly also in math or calculus 
What is the derivative of x^2?? 
What is the derivative of sine?? 
What is the integral of x^3??

Kinematics Which quantity is represented by v0?? 
Which quantity is represented by xf?? 
Which quantity is represented by t??

Force 
Which law gives the popular equation F = ma?? 
What is the name of the force which always points perpendicular to the surface on which an object rests?? 
How do you line up a force with a coordinate axis??

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December 16, 2015  

The one where your host finds goes through another volume of reviewing.

Check out the blog at pwnyourhw.blogspot.com for more! 

And if you're so inclined, grab an app or two or three here: https://itunes.apple.com/us/developer/elijah-hibit/id578486296

Oh, and the Facebook page now too: Facebook.com/pwnphysics

Give us a like, it would really help!

In this episode, we're pushing towards final time, and also towards episode 100, so we're taking stock of where we've been, where we are, and where we're going. For midterms and finals, it's so important to make sure the basics are under control, so here we roll through a little 3 question quiz for the following topics: Coordinate Systems, Sine & Cosine, SOHCAHTOA, Vector Components, Vector Operations. If you don't have the questions asked in this episode locked down please, please do yourself a favor and grab the apps or the bundle. This stuff is so important to know absolutely cold for your big exam!


  • Coordinate Systems
    • Which coordinate system has positions (x,y,z)?
    • Which coordinate system has position (r,theta)?
  • Sines, Cosines, By Counting To 4
    • What is the sine of 0? 0
    • What is the cosine of 0? 1
    • What is the sine of pi? 0
  • SOHCAHTOA
    • Which trig function is the ratio of Opposite to Hypotenuse sides of a right triangle? 
    • The tangent of an angle is equal the ratio of which two sides of a right triangle?
  • Components
    • How is a vector component related to a vector?
    • What identities or functions allow us to break vectors into components?
  • Vector Operations
    • How do you add vectors?
    • How do you subtract vectors? 
    • How do you multiply vectors?
    • How do you perform a scalar product?
    • How do you perform a vector product?
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December 10, 2015  

The one where your host finds the balance between thinking and doing.

Check out the blog at pwnyourhw.blogspot.com for more! 
And if you're so inclined, grab an app or two or three here: https://itunes.apple.com/us/developer/elijah-hibit/id578486296
Oh, and the Facebook page now too: Facebook.com/pwnphysics
Give us a like, it would really help!

In this episode, we're pushing towards final time, and also towards episode 100, so we're taking stock of where we've been, where we are, and where we're going. For midterms and finals, it's so important to make sure the basics are under control, so here we roll through a little 3 question quiz for the following topics: Greek Letters, Units Of Measure, Powers of Ten, Physical Constants, Unit Conversion, and Vectors vs. Scalars. If you don't have the questions asked in this episode locked down please, please do yourself a favor and grab the apps or the bundle. This stuff is so important to know absolutely cold for your big exam!
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December 2, 2015  

The one where your host finds the balance between thinking and doing.

Check out the blog at pwnyourhw.blogspot.com for more! 
And if you're so inclined, grab an app or two or three here: https://itunes.apple.com/us/developer/elijah-hibit/id578486296
Oh, and the Facebook page now too: Facebook.com/pwnphysics
Give us a like, it would really help!

It’s not so easy. So there are two fantastic aphorisms which hold a lot of water in my life. The first is “Work Smarter, Not Harder”. The second is “Stop Thinking, Start Doing”. These both hold a lot of power. Either can be wildly unproductive if not used properly. They can also both yield awesome results. There is a trick and balance to using them in conjunction which may not be so obvious. 

When I was working as an app developer, creating iPhone apps for insurance appraisal, sometimes I was faced with coding which I felt was a little out of my league. I would sit there and think, and think, and think about how to achieve a certain goal, and so I made a little sign for my wall: “Stop Thinking, Start Doing!”. It actually helped me out a lot. As I would sit there, and try to look at my problem from every angle, when I finally decided to get down to work, and just tackle the darn thing from any given side, I found that I was able to achieve my goal in a very reasonable amount of time. I let this be my motto in times when I was feeling burdened by overthinking. One day, I walked into my office to find that my sign had been replaced by one that said “Work Smarter, Not Harder!” This was my boss’s clever way of trying to encourage me. It was borne out of a wonderful place, and the work smarter not harder mentality had always been one that I had embraced, up until that moment when I found it replacing my other motto. It was at this moment that I finally had a realization. My boss had a mentality that these two sayings, and approaches to work are fundamentally at odds with each other. If I stop thinking, and start doing, I will be wasting lots of time cranking on problems that in a clumsy way that will yield me mediocre results, if only I had thought more! You can apply this to your next physics test. Imagine just reading the problem and starting to work without any discernible strategy. Just 15 seconds of pondering might illuminate pathways that cranking on a problem will never get you to.

Consider the flipside: your grade on your test is 100% dependent on whatever you write down on the test paper. If you wheedle away all of your time thinking about the best approache, especially in a timed setting, there won’t be much to show when it comes time to grade your test. 

The real talent, like with most things in life, is finding the balances between these two extrema. For me the breakdown was something like this: many of my physics tests were 4-5 questions, with 2 hours to complete. That gives you something like 20-30 minutes per problem. It’s actually not that much once you really start diving in, but it is a big chunk of time, if you know where you’re going. In this situation, I normally took the first 15-20 minutes to just read through each problem, taking in the problems, and understanding exactly what they’re asking of me. 

What topic from class is this question really trying to ask? What will my initial strategy be? How many parts are there in this problem? I might jot down some initial ideas on scrap paper, just so I don’t forget. While the rest of the class is feverishly writing away, I would be sitting, thinking, and making some attempt to work smarter, not harder. When you’re writing your mind is full. As much as most people don’t like to hear it, there is no such thing as multitasking. Either you’re thinking about what you’re writing down, or you’re thinking about the other problems. There’s really no in between. If you’re thinking about your other problems, you’ll be making mistakes on this problem. If you’re thinking about the problem at hand, you cannot be thinking about anything else on the “back burner”. Leaving some space to let the problems settle into your mind, and not jumping into action will really give you a chance to do a good job. 

After I have my initial strategies ironed out, working smarter is over. It’s time to stop thinking, and start doing. After all, they want to see writing on the paper. It doesn’t matter how well you’ve thought it out. So get to work! 

So with this in mind, even in a multiple choice type setting, I usually block out 12-15% of my time to work smarter, not harder, and the other 85-88% of the time to stop thinking, start doing. Believe it or not, most of the time I’d finish early.    

With homework, it’s a little tougher, because you feel like you have all the time in the world. Sometimes it’s useful to constrain yourself. Give yourself 2 hours to finish. Treat it like a test. You’ll be in good shape when exam time comes around! Try the 12-15% of the time to absorb the questions, then get to work! Pace yourself, and stop thinking, and start doing. That’s where all of these step-by-steps come into play. If you can think of the problem as being a sequence of step by steps during your work smarter period, the stop thinking, and start doing time will be a breeze. You’ll be going through the motions. 

Balance is critical. You need to understand what works for you. This guideline worked very well for me. You may need to tweak it a little to get it just right for you. But, going in with a strategy will give you a much better chance at a good outcome than just scrambling through your test. Remember, work smarter, not harder!

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November 18, 2015  

The one where your host tells you all about the devil in the details: 

Check out the blog at pwnyourhw.blogspot.com for more! 
And if you're so inclined, grab an app or two or three here: https://itunes.apple.com/us/developer/elijah-hibit/id578486296
Oh, and the Facebook page now too: Facebook.com/pwnphysics
Give us a like, it would really help!

Let’s throw another reason on the already monstrous pile of why most people hate physics. Not only do we have a very non-intuitive mind-bending type of logic which describes our world, but put on top of it, that the nature of our universe is very precise. Objects and particles behave and move with high calculable precision, that’s it’s best and worst quality. Humans are pattern seeking mammals and above all tool users. A long long time ago, our ancestors were able to take advantage of something that has easily made us the dominant force on the planet: the universe is a repeatable place. Patterns exist. Animals migrate and behave according to patterns. Tools are a natural extension of this. If we can understand how something works, it is very easy to either use it as a tool, because the performance is repeatable, or exploit it in a way that is highly reliable. This has come to fruition in recent centuries in the form of manufacturing. We can now produce immense quantities of items by taking advantage of interchangeable parts, physics, a large population which needs similar items to support itself. All of these things are just patterns expressed in different ways.  

The ultimate goal in physics is the GUT, or Grand Unified Theory, a.k.a. the Theory of Everything. Potentially the ultimate purpose or use of this species: the grand-daddy of all patterns. As we make our way towards some GUT, if there is one, the patterns we utilize and look for are becoming vastly more complex. Even calculus, which is roughly 400 years old, is something most people can’t even begin to wrap their minds around. 

This is the conundrum of our universe: the pattern seeking mammals struggle to see the patterns in it. Physics has a beauty that is very easy to convey to anyone, once of course you remove most of the mathematics. Simply describing how things work: throwing an object on Earth roughly follows the shape of an arch, or parabola. The planets orbit the sun in a circular, or sometimes elliptical orbit. These ideas are fascinating to even children, and children want to know very much why these bodies behave this way. Then you start to explain it. “Well ok, so you have the force of gravity, which is about 9.81 m/s^2, and you have to consider the angle of 42.5 degrees, and the initial velocity of how many m/s?” You start to lose people. Start throwing these values into equations, and it’s over. Unless you’re talking to physics majors, and then it’s not so bad, but you can still lose everyone if you’re not careful. And it’s not that physics majors, or even your average person isn’t smart. Most people are very smart. It’s that the actual patterns that exist around us are very counter-intuitive, and difficult for our jelly-filled brains to take hold of.

On most physics tests, even non-majors can get started off the right way. It’s when we start doing too much too fast, or get careless that most of the points are lost. Any small mistake in the tens or hundreds of individual simple calculations that need to be done can give a wildly incorrect final answer. One decimal point gives you ten or hundred times more or less. One rounding error can throw your final answer off enough to take 20 points off a test. And it’s not just tests. Using the wrong units means that a lander crashes into mars at unbelievable speeds instead of landing like a feather. 

That is why what we’re doing at this point of the podcast is so important. Learn the fundamentals. Pay attention to the little details. Master these tools. You will have to use them in crazy combinations one day, and there will be an expectation to do it perfectly. It could mean destroying tons of machinery, or an entire letter grade on your final exam. The stakes are high. If you can whittle the problem down into a series of manageable steps, it won’t seem impossible. And, if you can take extreme care, and focus, and think only about the step you’re working on right now, you will be able to take a thousand doable steps to traverse a leap you never thought you could. 

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November 4, 2015  

The one where your host crosses c x d and d x c to prove that c x d is indeed equal to -(d x c). 

Check out the blog at pwnyourhw.blogspot.com for more! 
And if you're so inclined, grab an app or two or three here: https://itunes.apple.com/us/developer/elijah-hibit/id578486296
Oh, and the Facebook page now too: Facebook.com/pwnphysics
Give us a like, it would really help!

One thing that we can notice, is that 

c x d = -(d x c)

Is it possible to prove this? In order to verify, let’s perform the exact same steps with two vectors [cx,cy] and [dx,dy]. First let’s calculate c x d

Step 1: Identify Two Vectors in Coordinate System as [ax,ay] & [bx,by]- These are given in the problem as [cx,cy] and [dx,dy]. For later reference, let’s identify each component: 

ax = cx

ay = cy

bx = dx

by = dy

Step 2: Multiply ax and by- Here we can easily reference step #1 and perform the following operation: 

ax * by = cx*dy

Step 3: Multiply ay and bx- Here again we can easily reference step #1 and perform the following operation: 

ay * bx = cy*dx

Step 4: Subtract step 2 from step 3, i.e. ax*by-ay*bx: 

cx*dy-cy*dx

Step 5: Place a k-hat at the end and box your answer, you’re done!

So our answer is:

(cx*dy-cy*dx)k-hat

Next, let’s calculate -(d x c). In order to do this, we’ll simply calculate w x v and then multiply by -1. 

Step 1: Identify Two Vectors in Coordinate System as [ax,ay] & [bx,by]- These are given in the problem as [dx,dy] and [cx,cy]. Notice that they are reverse this time. For later reference, let’s identify each component: 

ax = dx

ay = dy

bx = cx

by = cy


Step 2: Multiply ax and by- Here we can easily reference step #1 and perform the following operation: 

ax * by = dx*cy

Step 3: Multiply ay and bx- Here again we can easily reference step #1 and perform the following operation: 

ay * bx = dy*cx

Step 4: Subtract step 2 from step 3, i.e. ax*by-ay*bx: 

dx*cy-dy*cx

Step 5: Place a k-hat at the end and box your answer, you’re done!

So our answer multiplied by -1 is:

-(dx*cy-dy*cx)k-hat

=(-dx*cy+dy*cx)k-hat

=(cx*dy-cy*dx)k-hat

So, not a full proof, but very convincing nevertheless. It turns out that this is actually true in all cases, in 2-D and all higher dimensions. 

In order to explore the cross product deeper, we will now perform the same example, but with 3-D vectors, which will have a single new number as our z-coordinate.   

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October 31, 2015  

The one where your host takes you through #6-4 of 9 unsolved mysteries in physics! 

I came across this incredible article from livescience.com entitled "The 9 Biggest Mysteries in Physics", as I was infosnacking on Twitter. It's a great article and really embodies where Physics is headed in the next 25 years, if we can even answer one of these questions with any degree of certainty. In this episode we discuss #6-4 in some detail, since as budding physicists, this are the monster questions you have to grapple with. Good luck! 

Blog: pwnyourhw.blogspot.com

Article: http://www.livescience.com/34052-unsolved-mysteries-physics.html?cmpid=514627_20150817_50959276&adbid=633345100534280192&adbpl=tw&adbpr=15428397

Apps: https://itunes.apple.com/ca/developer/elijah-hibit/id578486296
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October 30, 2015  

The one where your host takes you through #6-4 of 9 unsolved mysteries in physics! 

I came across this incredible article from livescience.com entitled "The 9 Biggest Mysteries in Physics", as I was infosnacking on Twitter. It's a great article and really embodies where Physics is headed in the next 25 years, if we can even answer one of these questions with any degree of certainty. In this episode we discuss #6-4 in some detail, since as budding physicists, this are the monster questions you have to grapple with. Good luck! 

Blog: pwnyourhw.blogspot.com

Article: http://www.livescience.com/34052-unsolved-mysteries-physics.html?cmpid=514627_20150817_50959276&adbid=633345100534280192&adbpl=tw&adbpr=15428397

Apps: https://itunes.apple.com/ca/developer/elijah-hibit/id578486296
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October 30, 2015  

The one where your host takes you through #9-7 of 9 unsolved mysteries in physics! 

I came across this incredible article from livescience.com entitled  "The 9 Biggest Mysteries in Physics"(click for link), </a> as I was infosnacking on Twitter. It's a great article and really embodies where Physics is headed in the next 25 years, if we can even answer one of these questions with any degree of certainty. In this episode we discuss #9-7 in some detail, since as budding physicists, this are the monster questions you have to grapple with. Good luck! 

Blog: pwnyourhw.blogspot.com

Article: http://www.livescience.com/34052-unsolved-mysteries-physics.html?cmpid=514627_20150817_50959276&adbid=633345100534280192&adbpl=tw&adbpr=15428397

Apps: https://itunes.apple.com/ca/developer/elijah-hibit/id578486296

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October 28, 2015  

The one where your host crosses products both backwards and forwards. 

In this episode we explore dot product and cross product operations in depth with more examples. First, we do a real physics problem! We dive into W = F dot d, where W is work, F is force, and d is displacement. Next, we do a straightforward 2D cross product example, but in two directions. First we calculate c x d, and next d x c. What do we learn from this??
Check out the blog at pwnyourhw.blogspot.com for more details, and if you're feeling like you want some review apps, do check out the app page here: 
https://itunes.apple.com/ca/developer/elijah-hibit/id578486296
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