Thursday, April 28, 2011

"Independent" Research Projects

BOAT: We chose the project to do the clay boats and hot air balloons. They float because of the density of air and buoyancy to float on the water. Buoyancy is the force equal to fluid...the weight of the displaced fluid. It is the upward force and keeps things floating. An object will float if the buoyancy is greater then the weight. We found the weight of the displaced fluid. We placed the boat in a container filled to the very top with water and formed a meniscus. When the boat was placed in the water, water spilled into a larger container and the this was the water the boat pushed out. Our little boat was 67.17 grams and the water it pushed out should have been equal to the boat. The water pushed out was 70 grams.

BALLOON:Denisty is: Mass/Volume Denisty is a physical property of matter that expresses a relationship of mass to volume. The denser, of two equal volume objects will be heavier. We made a hot air balloon with tissue paper, glue, templates and paper clips. We followed all the directions and created a balloon. We used the Indoor Balloon Tester and the pressure of the air pushing the balloon up made it float.

ARCHIMEDES: Archimedes Principle states:An object immersed in a fluid is buoyed up up by a force equal to the weight of the fluid displaced by the object. Knowing mass and volume of an object allows to calculate density.

Thursday, April 7, 2011

Video!! :)

Electromagnetic Spectrum...

1. The electromagnetic spectrum is different types of radiation, such as cooking in the microwave, listening to the radio, or taking an X-ray. Their is also visible, which is looking at the stars or anything that we can see. The visible spectrum is taking a white light and shining it through a prism, all the colors of the rainbow spread through and you can visibly see the rainbow from the reflection of the white lights. The microwave, light we see and much more are all parts of the electromagnetic spectrum...and we even use a part of the electromagnetic spectrum using our phones everyday.
2. Light is the speed of all forms of electromagnetic radiation. The speed is 186,282 miles in a vaccuum and a little less in a material medium. No matter the frequency, wavelength or intensity of the radiation, the speed of the light will always remain the same.
3. The ways to split the spectrum to see different parts is by wavelengths. Each part of the spectrum is split up by their wavelengths, frequency and energy levels. The charts above show that each part of the spectrum is determined by their wavelengths.

4. For radiation to reach the Earth from the Sun, it takes:
The Earth is 150 million km. from the sun. Radiation from the sun travels 300,000 km/s. Time=Dist/Speed so 150,000/300,000=500 seconds or a bit over 8 minutes.

5. For light to reach Earth from the next closest star, it takes about 4.2 light years or 4.2 years.

6. The primary colors for T.V's, computers and stage lighting are red, blue and green.

7. The primary colors for the printing industry (paper, magazines and cereal boxes) are cyan (blue), magenta (red), yellow and black.

8. When we look at images through different lenses and mirrors, the images may not show up becasue there is not enought light OR too much exposure. Also, the distortion of the angle the camera or mirror is may affect how the image looks.
Mirrors-Concave mirrors: bend away at the middle
             Convex Mirrors: bend away at the edges, produce virtual, erect and reduced images
             Plane Mirrors: image is virtual and same size as the object in the mirror
Lenses- Wide-Angle: Get closer to the object
             Standard: Same magnification as the human eye.
             Telephoto: Brings the image closer and compresses the perspective
9. An important scientist dealing with the spectrum is James Clerk Maxwell. He developed a theory to explain electromagnetic waves. Electric fields and magnetic fields came together to form electromagnetic waves. An electric field and magnetic firld would not do anything on its own, so he realized changing one of the fields would induce the other. Electromagnetic waves happen when changing the magnetic field causes a changing electric field...and continues. A wave doesn't exist unless its moving and the wave conitnues on unless its absorbed by matter.