A Spectrum of Radiation

        The different types of radiation, or the electromagnetic spectrum, is energy that can travel through a vacuum or matter in waves.  This type of wave does not need a medium.  The specific types are radio, which are the longest, and then in between visible, infrared, ultraviolet, x-rays,microwaves, and gamma-rays being the shortest.  But for now, that's all just names. Each wave in the spectrum names a different portion of wavelength, with the waves traveling from places like the earth to the universe!  But the lengths are also very important, I mentioned earlier that the radio waves are the longest starting around 8x10^6m to 3x10^0m, and then going down in the order microwaves, infrared, visible, ultraviolet, x-rays, and then gamma-rays with the starting length of about 1x10^-10m.

radio tower

 black hole

        Radio waves are, in my opinion, some of the coolest waves there are.  We listen to music on radio waves, TV and ship signals, and also, the most interesting, stars.  The wavelengths, in more relative terms,  ranges from a bus length to the distance between the earth and moon.  That's really long!  So you've heard about the length a lot by now, you may be wondering what happens when we use it for radio broadcasts.  We use the earth for our mighty music and S.O.S.'s.... we use the ionosphere!  The ionosphere is part of the upper atmosphere and reflects some certain radio frequencies, allowing us to use it for longer distances.  Earlier, I motioned stars.  Stars, along with lighting and sparks, emit radio waves, usually causing interference in whatever we happening to be listening to on the radio.  Too many frequencies of radio waves will cause interference with each other and scramble things up. To solve this problem, the Federal Communications Commission monitors and traffics the waves, restricting the number of users of a certain frequency.

     The other wave that I think is also cool is infrared.  Infrared waves are just past the visible spectrum and we use it for so many cool things like changing the channel on the TV, but also for thermal imaging and astronomy.  We use infared in termal imaging because usually, infared waves show heat, when used by a special sensor.   Things, such as ourselves, lamps, and fire are found with these sensors.  That is one way we can see the stars otherwise hidden behind the dust in that nebula.   The infrared wave is very useful to other things besides looking at far away nebulas.  It is very useful for short distance signals, such as a remote and TV as metioned earlier, and even walkie-talkie head sets.

        The Electromagnetic Spectrum is a variety of waves and clasifications, letting us learn about the secrets of the universe and other things.

http://missionscience.nasa.gov/ems/01_intro.html

http://school.discoveryeducation.com/lessonplans/interact/electromagneticspectrum.html

http://www.darvill.clara.net/emag/index.htm

ENERGY, ἐνέργεια, Энергия, 能源, Energi (in whatever language you want), it's in Everyday Life

       Energy is a conserved quantity that can change.  It can be transfered from one method to another and also stored in many other ways but it always remains the same amount.  There is elastic, gravitational, kinetic, and potential energy.  Work can be imputed to show the change in the net force as well.  Energy is not just used in physics textbooks, but in everyday life, such as.........   ROCKETS!!!!!  

Helpful Hint: on the glogster the text is large so it is easier to read, that means less space so in every text box you have to scroll.


Rockets Energy Glogster



Picture taken from blog "Les Blog more Art!'

Universal Gravitaion and UCM or other words, gravity and things that go in circles

UNIFORM CIRCULAR MOTION

Definition - The motion of an object in a circle with a constant or uniform speed.


       Uniform circular motion does not have a constant velocity (due to direction change) and an ever-changing acceleration.  This acceleration due to the centripetal force. (centripetal means inward force that is applied to an object to keep it moving in circular motion, or towards the center.)  Circular motion depends directly on centripetal force and the centripetal force requirement depends on the force that keeps the object in a circlet.  The net force of centripetal force depends on the acceleration, and velocity as well. 


UNIVERSAL GRAVITATION


Definition (or the law of universal gravitation) - "every object in the universe attracts every other object in the universe with a force that varies directly with the product of their masses and inversely with the square of the distance between the centers of the two masses"


       The universal gravitation is the numeric value of 6.67x10^ -11 N.m^2/kg^2.  This figure is most commonly used in the equation Fg= (Gm1m2)/r^2


WHAT I HAVE LEARNED....


I have learned that there is an equation to find the gravity of other planets or imaginary places, but that I already at least new a little about.  The thing I learned that was the most 'enlightening' was learning about circular motion.  I did not know that uniform circular motion was always accelerating and I did not know that it did not have a constant velocity.  It does not have a constant velocity because although the magnitude is constant, the direction is always changing.  As our book tells me, this word that describes it is tangential.  Also with uniform circular motion there is period T, frequency, and acceleration.

WHAT I HAVE FOUND DIFFICULT ABOUT MY STUDIES IS....

What I have found difficult is remembering what equations to use, also I have trouble 'improvising' with things such as coefficient of friction but now, after studying for the test, I now understand what to do.  I also used to have trouble with ratios but not anymore (since I studied for the test.)

MY PROBLEM SOLVING SKILLS....

My problem solving skills have needed improving, I lacked some of the connecting to improvise and impute other equations when needed.  But since studying for the test, I feel like I have improved and understand more of what is really going on in these equations.  Some of my strengths are being able to solve with no problems when I have the equations.  An example is the ratios problem on page 106 in the blue notebook.  It asks to find the value of g if earth's mass was double but the radius remained the same.    I couldn't think of the equation to use.  It didn't occur to me to use the equation that Mrs. Gende gave me because I thought I needed to make a ratio problem.  I made a equation that worked for all the problems and some others that needed to be worked on the notes.  Later Mrs. Gende told me that it wasn't a good equation to use.  And to only use the equation g=GM/r^2.  But in this equation with G is equal to 9.8m/s (with mass as well so mass is canceled out) and when multiplying the other side of the equation is is 9.8m/s,.  The other problem was 43 on page 105.  And I used my equation that I made to solve this problem....  But after speaking to Mrs. Gende I tried that other equation and it worked as well, I was just trying to solve a problem and so I did what I could to solve it.

Mythbusters Lab

MYTHBUSTERS

           This Mythbusters episode is focusing on two myths today.  Each has one experiment, one regular video with an explanation and a cooler video that doesn't explain everything but is fun to watch anyway.


Also; the small, unnamed arrow means the direction in which the ball is traveling.


Myth #1
        An object always moves in the direction of the net force exerted on it.


If the object always moves  in the direction of the net force and a basketball is thrown in one direction, then it will keep going in that direction.

Video (plain)

This FBD shows projectile motion, the ball is simply thrown forward.

The ball now moves back toward the person that threw it but the net force shows that it should still be going down.

Conclusion;
          As seen in the FBDs the ball continued forward like normal projectile motion but when it hit the ground, according to the 'myth' it should have stopped.  But it moved back up forward with the net force in a downward direction.  This theory is not always true and therefore disproved.  BUSTED!
         Most people believe this myth because it is usually true.  Most of the times it is not then most people regard it as another force acting on it that they don't understand.  It also gives a rational reason for why things are the way they are and people will put their trust in something that is mostly true if there isn't anything that can be all true.






Myth #2
        An object always changes its motion if there is a force exerted on it by other objects.


If an object always changes in motion if there is a force exerted on it by other objects then a ball rolling toward a container should change direction when it hits it.

Video (plain)

This is the FBD of the ball after it has left the foot so no other applied force is acting upon the ball.  

As can be seen, the direction of the ball didn't change even though another force is acting upon it.

The ball didn't change direction even though it hit the container.  The second FBD disproves the myth by showing that even though other forces were exerted on it it did not change direction to conform to those that force.

Conclusion;
          The ball did not change its motion even when another force acted upon it.  Even though it was a small force, it still did not change therefore disproving the theory.  The before equation is BUSTED!
          This myth is believed anyway, even though it can be disproved, because, usually it is true and it also deepens, if a person gets really specific on angle, a very small force can change the direction of the object.  This myth explains many things in our world and it is much simpler to believe in what is mostly true and try to apply it to all.(at least all relating to the subject)




Awesome video to myth #1;

Awesome video to myth #2;

Oh Come all ye Willing (physics carol)

For the physics carol extra credit I am in a group with Jasmine(also singing) and Abigail(recoreder playing).  We are doing it to Oh come all ye faithful.

Oh come all ye willing,

To learn of physics filling,

of forces and velocity, plus FBDs.

Action reaction,

opposite in direction,

bug hits windshield and windshield hits.

gravity and free fall,

it affects us all.

9.8 m slash s squared - a rate that makes us scared.

(and possibly)

Velocity and speed,

different types of motion,

speed is only magnitude,

velocity needs direction.

From this arises,

projectile motion,

x and y components,

with distance postition.

The Laws of Motion

       I leaned that there are three main laws of motion, having to do with the forces and motion.

 The first law states that ‘an object at rest tends to stay at rest and an object in motion tends to stay in motion,’ if it is in constant velocity and direction (translational equilibrium) unless acted upon by other unbalanced forces. Or in other words, it helps to predict what is going to happen.  Some other things that a beginning scientist needs to know are units, mass, and weight.  The units are measured in a metric system called a newton (science is always metric). A Newton is the force needed to give one kilogram a one meter to second squared acceleration. Mass is a quantitative measure of inertia, and example is if a one kilo object on earth goes to the moon, where gravity is different, the mass will be the same, it is the weight that is different.

        The third law states that ‘for every action, there is a reaction.’  It is equal forces acting on multiple objects (usually two but sometimes on multiple spots) but opposite in direction. Newton’s second law says that if there is a force that where the net force remains unbalanced, then the object has acceleration.  The acceleration also changes with direction. 

      The second law is about acceleration of an object in the direction of the applied force and explains cause and effect.  For example, if the acceleration is constant, and the sum of the forces remains the same, the mass is a certain amount.  If the mass is doubled, then the acceleration is cut in half because “the acceleration of an object is proportional to the net force and inversely proportional to the mass of the object.”

      What I had found difficult in these studies is finding the equation for calculating the forces from the FBDs. (Especially when on an incline.) 

      My weaknesses are trying to build the equation on some problems (mainly first law (and in that mainly when it is on an incline)) and to figure out what needs to be positive and negative. I think I am trying to rely purely on memorization and fail to get fully the steps to building my own equations. It helped when in the second law we started to put the positive and negative signs.  And I am now able to build the equations without getting mixed up on which to add and which to subtract.

When I shoot things out of a cannon and all the mathematics components that come with it.

     I learned many wise things while in Mrs. Gende’s class in the past few months.  But this time I will comment only on when I shoot things out of a cannon and all the mathematics components that go with it(a.k.a. Projectile motion and vectors).

      I learned that theta the symbol for an angle, (or θ) is all about trigonometry and vectors.  There are many ways to find theta, and other aspects of trigonometry and projectile motion, but almost every equation has to do with theta of some form.

      Vectors are force, displacement, velocity, and acceleration. A vector is a quantity possessing both magnitude and direction.  Vectors are usually indicated by the direction and the length proportional to magnitude.   Where x is horizontal and y is vertical.  In this unit, we mainly use the vector form of projectile motion.

      Projectile motion has to do with horizontal motion and vertical motion (vertical motion has to do with gravity).  I learned cool things like the fact that the velocity of horizontal motion is constant and the initial velocity of vertical motion is always zero.  But only in the specific projectile motion.  When it is changed to projectile motion at an angle, the initial velocity can vary.

      What I found difficult is knowing when I needed to use the x-components and y-components.  My problem-solving skills have developed over the course of this section and I have come to recognize which equations to use and how to use them to find the other variables. My only weakness comes to recognizing which equation is which on the equations sheet.

 The connection between everyday life and what we studied is having the subconscious knowledge of how to do things like projectile motion. For example, in soccer, if I wanted to score a goal (no counting the goalie) I would think (in a matter of seconds) how hard I would need to kick the ball (velocity) and imputing the gravity (or the arc formed by Gravity), what angle I need to kick it so it will go into the goal in the air. That, in every way, is projectile motion.