I Hate to Sound Dense, but...

As with light, so with sound. Well, not always, but there are a few parallels, and one of those parallels is speed. The material (or medium) that sound passes through affects its speed. How so?

For a benchmark, let's use the speed of sound in air at the beach in Malibu on sunny, 70-degree day -- 1,125 feet/sec (666 mph), also known as Mach 1.

How will the speed of a given sound change (FASTER, SLOWER, NO CHANGE) in the following scenarios:

...on top of Mount Everest?

...submerged in a pool?

...through a wall?

...in Florida (same air temperature as Malibu, at sea leavel, but much more humid)?

...in space?

Excluding space, pick the option above that you think will transmit sound waves fastest, and explain WHY.

It Takes Two to Tango -- Temperature and Pressure!

Having watched the Mythbusters, Adam & Jaimie, release the full force of a PRESSURIZED WATER HEATER on a runway overlooking San Francisco, there clearly exists a link between heat and pressure. But what is it?....That's my question to you.

How are pressure, heat, and volume related and dependent on one another? Give me some "for example"s.

Be reasonably thorough in your explanation, which should be at least a couple of GOOD sentences long.

(BTW i think that sentences like this 1 r beneath u and that u should take the time to present ur best work. in other words show better punctuation capitalization and care in the work u produce and ur written communications. just like we established at the beginning of the year i will start taking off points for poor sentences on ur blog work as well as ur quiz responses. better find that "shift" key! if ur still reading good for u b/c to get full credit on this assignment u need to include a smiley face (a colon & parenthesis r fine) in ur blog response. ☺

My Brain has a Mind of Its Own!

Just like we talked about in class, our brain does a lot that we're not aware of to make sense of the constant stream of sensory input it receives. Watch the video and participate in it (best in full screen mode), and READ the whole article (it's short!) describing the phenomenon.

http://games.yahoo.com/blogs/plugged-in/video-optical-illusion-wins-head-191105551.html

Crazy, right?! For your reply, since I can't ask a follow-up question specific to this topic, all you have to do is briefly state 1. something nice that someone did for you today and 2. something nice you did for someone else today.

If you can't think of anything for #2, the day isn't over, so go practice a random act of kindness, no matter how small. ☺ Cool beans!

2-for-1 Special!!! Space-Time

Space-time is kind of a big deal. As we discussed in class, when distorted by matter (massive bodies like planets, moons, etc.), it creates the sense of gravity. Earth's gravititational tug-of-war with the moon in turn is responsible for causing the Earth's tides. Gravity also causes light to bend, streeeeeetching our perception of time.

Don't worry!....both concepts take awhile to get one's head around. Here's your assignment:

Watch the video (to the right) about space-time AND watch the full animation about tides (http://www.onr.navy.mil/focus/ocean/motion/tides1.htm) -- the total viewing time is less than 5 minutes. Then post a SPECIFIC question you have about EACH concept that you want answered in class.
(That means two questions from everyone. Oh, and by the way, "I don't get space-time?" doesn't count as a good, specific question!) ;)

We'll discuss your questions in class during our next meeting and get to the bottom of these topics.

Centri-WHAT?!

We've discussed two new forces recently that aren't actually "new" or "forces." Centrifugal "force" is your perception of inertia/momentum's effect on you when going in a circle -- there's no actual force pushing you outwards.
Centripetal force isn't a "new" force at all, but simply a description of whatever happens to be holding something in its circular motion -- gravity, tension, air pressure, etc.

Riddle me this, what is the cetripetal-type force that allows a car to go around a turn rather than flying off in a straight line? Briefly explain why/how the force acts in a centripetal ("center-seeking") manner.

Hint: What matters most is where the rubber meets the road.

 

 

The Power of Rube!!!

Reuben Goldberg was an American cartoonist who's wild cartoons showed crazy contraptions doing simple tasks. His cartoons have since inspired countless people to challenge their creativity and their understanding of physics in the real-life production of simple yet complex machines. Fun, imagination, and physics are key.

The simple pattern

ENERGY -- FORCE -- ENERGY -- FORCE -- ENERGY -- FORCE -- ENERGY.......

Start by reviewing the week 6 notes online (this is a mandatory part of the assignment).



Watch the large video (to the right) and find examples for the following six concepts. BE SPECIFIC and briefly explain why your examples demonstrate the concepts.

Static Friction
Kinetic Friction
Work
Gravitational Potential Energy
Elastic Potential Energy

Kinetic Energy

Phun Physics with Phelines!

Hope you all are cat lovers. I've always been more of a dog person, but there was no video called "Dun Dysics with Dogs." Watch the video (at right) and share something you learned from it? Be detailed and accurate in your response...."I learned about friction" isn't the kind of response we're striving for. You all did a fantastic job with your responses on the last blog post -- keep up the great work!

:) Mr. R