Waves Lab

Science Lab Materials: • Ripple tank filled up with water • Pipette • Styrofoam ball • Clay sticks Making Waves Hypothesis: I hypothesize that, whatever drop is released to fall in the ripple tank it will cause waves which will cover the whole area that is given; in this case it is the ripple tank. Data Analysis In the first part of the experiment, where the waves were created by the drop of water released from about 10 height, the waves in the ripple tank behave according to the place where they have been produced: if the wave was created in the center of the ripple tank, it traveled in the form of concentric circles until it reached the edges of the tank. If the waves were produced in the corner of the ripple tank, or in the middle of the ripple tank’s side, they traveled in a form of semi circled ripples, also reaching the very opposite end of the tank. When the waves were created In the corners, center, and at one end of the tank as well, they started to spread either as circles or semi circles; but when they collided they canceled out each other and interrupted each other’s movement. In the second part of the experiment, interaction between waves and barriers was observed. Whichever wave was produced, it traveled under the floating paper towel or under the Styrofoam ball. However, when a solid object i.e. stick of modeling clay, was placed in the tank the waves started to splash the edges of the clay stick. When the two clay sticks were placed so that a gap of about 2 cm was created, the waves travel as semi circles until they reached the barrier and then split into smaller waves and pass between the barriers using every possible passage to continue their movement. On the other hand, no matter how many Styrofoam balls were placed next to each other on the water surface, and no matter in which part of the tank the waves were created, they would always move under the floating objects lifting them slightly, without interrupting their own movements. Conclusion In every phase of the experiment waves showed the ability to travel as far as the end of the tank, even when they were interrupted by solid objects placed shortly apart from each other. Their shape depends of the place of their creation: if they were created in the middle of the tank, they formed full concentric circles, while the ones formed in the corners or at the ends were forming concentric semi circles. Waves have the property to transform the mechanical energy which was used to create them i.e. the energy of a drop of water falling on the water surface is further transform into wave energy. Also, the higher the amplitude and faster the frequency, the bigger/stronger the waves are. As for the waves interaction with each other and in with the solid objects in their paths, when colliding with each other waves tend to cancel out each other’s movements.

Moon Phases

Guiding Question: What are the phases of the moon?  Why do they occur? 
Hypothesis:  I predict that all of the sides that the moon is turned that the half of thye moon will be lightened.  
Materials: 

• One big Styrofoam ball
• one  small styrofoam ball
• a toophpick
• a barbaque stick
• a torch
• and a ruler 

When making bthe expiriment today we had to gather the materials, which would represent a planet or body in space. The big styrofoam ball represented the planet Earth, which was stuck on the stick, in order to hold it without touching the styrofoam. On the big styrofoam ball was attached by a toothpick a small sturofoam ball which represented the Earhts moon. The torch represented the sun, and the ruler we had to use so we can measure the distance between the sun and the Earth, which was 30 centimeters for the model and in real life it is 149, 597, 870.7 kilometers. What i would do to resolve this question i rotated the earth slowly around to see what will happen, and I have noticed that when it is day on Earth, we see only the dark side of the moon, and when it is night we see the lighted part of the moon, which lets us see the moon. And when the moon is one of hemispheres like the west or east hemisphere, the moon will be a crescent moon. The moon changes its phase every month, due to its rotations.

Equanoix and Seasons Expiriment

Problem: How does the tilt of the Earth's axis affect the light received by the Earth as it revolves around the sun.

Hypothesis: My hypothesis is as the Earth rotates on its axis there is night and day. Because the Earth is tilted the when on one side the sun shines on the North Pole, in the South Pole it's dark, and also the other way round. The stick which used as an example is going to change length as it rotates.

Experiment: The Earth is tilted 23.5 degree, so, we made a model out of a Styrofoam ball, and we used a pencil to stuck it properly, while the toothpick was used as an axis. The flash light was representing the sun, while the little grid line was put in front of the flash light. My observation was: as we moved  the flash light from the away ball, the grid lines were getting bigger and less visible at the North Pole, while at the equator the lines were more visible and defined. As we brought the grid closer the lines got much more visible at the equator but less visible at Poles. I noticed that when the light is pointing directly to the equator, the grid squares were having the shape of a square, while as you go more to the north the squares were getting more stretched and became more rectangle shaped. This happens because where the light rays are stronger they will produce sharp, well defined shades, and where there is less light the squares will be less visible and sharp. In the real world, where the Sun points directly to the Earth the light will be the strongest. This happens because our Earth has an axis which is an invisible line that goes right through the Earth. This is the reason that we have seasons, without the axis we wouldn't have them, we would just have summer and winter equinox.This is also the reason why there is permanent Summer on the equator and why the Poles have very short and cold summers. 

NEW PLANETS DISCOVERED IN NEW YEAR OF 2012

 NEW PLANETS DISCOVERED IN NEW YEAR OF 2012

NASA's Kepler mission has discovered 11 new planetary systems hosting 26 confirmed planets. Such systems will help astronomers better understand how planets form.

The planets orbit close to their host stars and vary in size from 1.5 times the radius of Earth to larger than Jupiter. Fifteen are between Earth and Neptune in size. Further observations will be necessary to find out which are rocky like Earth and which have thick gaseous atmospheres like Neptune. The planets orbit their host star once every six to 143 days. All are closer to their host star than Venus is to our sun.
Prior to the Kepler mission, we knew of perhaps 500 planets outside of the Solar System across the whole sky. Now, in just two years staring at a piece of sky not much bigger than your fist, Kepler has discovered more than 60 planets and more than 2,300 planet candidates. This tells us that our galaxy is absolutely loaded with planets of all sizes and orbits.
Kepler identifies planet candidates by repeatedly measuring the change in brightness of more than 150,000 stars to discover when a planet passes in front of the star. That passage casts a small shadow toward Earth and the Kepler spacecraft.
By exactly timing when each planet passes its star, Kepler discovered the gravitational pull of the planets on each other, confirming the case for 10 of the newly announced planetary systems. Five of the systems (Kepler-25, Kepler-27, Kepler-30, Kepler-31 and Kepler-33) contain a pair of planets where the inner planet orbits the star twice during each orbit of the outer planet. Four of the systems (Kepler-23, Kepler-24, Kepler-28 and Kepler-32) contain a combination where the outer planet circles the star twice for every three times the inner planet orbits its star.
Kepler-33, a star that is older and more massive than our sun, had the most planets. The system hosts five planets, varying in size from 1.5 to 5 times that of Earth. All of the planets are placed closer to their star than any planet is to our sun.
The features of a star provide clues for planet detection. The decrease in the star's brightness and length of a planet’s journey combined with the features of its host star present a recognizable mark. When astronomers detect planet candidates that exhibit similar signatures around the same star, the possibility of any of these planet candidates being a false positive is very low.

Giant Beaver's Bleeting

During the Earth’s history there were many ice- ages, and the last one lasted between 70,000 to 10,000 years ago. During that period many of the today’s animals had their huge versions, which looked more or less the same, but they often had a different anatomy.  One of such examples is a giant beaver, which lived in North America and got extinct 10,000 years ago. Unlike today’s beavers the giant beaver had an extra cavity in its head, spreading from the front to the back of their skull. After examining giant beaver’s skull, using CT scan (X-ray images taken from many different sides of an object to create a 3-D image) scientists came to the conclusion that this special cavity’s purpose was to produce sound in order to provide a way of communication between the beavers. One of the scientists blew a note in the cavity and described the sound as a bleating, although the exact sound cannot be produced because the soft tissues were missing. Scientist said that this type of skull cavity is unique to giant beavers.

Measuring Rabbit population

In class we did this lab which was about counting the rabbit population over a period of five years but not real five years.

Dreams Measured for the First Time

Dreams Measured for the First Time

 Have you ever wondered what happens in our brains while we are dreaming?  How the images and feelings that we experience when we dream shape in our heads remains a mystery. Well, scientist now can measure our dream content. In Germany, scientists from Max Planck Institute have now succeeded:  the brain activity during dreaming could be analyzed. They found the way how the brain activity can be measured when dreaming. They chose lucid dreamers, who can dream voluntarily and are aware of what they are dreaming, and are even able to change the content of their dreams. They were asked to "dream" that they were repeatedly clenching first their right fist and then their left one for ten seconds. This was a sign of what do they dream. Methods like magnetic resonance imaging allowed scientists to picture and recognize the precise location of brain activity during sleep.  This enabled the scientists to measure the beginning of the REM sleep - a phase in which we dream the most intensively - with the help of  electroencephalogram (EEG), which measures brains electromagnetic waves. The movement during a dream, controlled by the sensorimotor cortex of the brain, which is responsible for the performance of actions, matched the one observed during a real movement in a state of awareness. Even if the lucid dreamer just imagines the hand movement while awake, the sensorimotor cortex reacts in a similar way. The matching of the brain activity measured during dreaming and the aware action shows that dream content can be measured.  Obviously, our dreams are not just a 'sleep cinema' in which we merely watch an event passively, but involve activity in the areas of the brain that are related to the dream content.