Phases of the Moon

The Moon has Lot's of phases it goes through in the 29 days it takes it to revolve around the earth. We explored all these phases in numerous ways, first with a flash light which represented the sun shining on to small Styrofoam balls which represented the Earth and moon. The moon moved around earth and the sun light affected different parts of the ball. We also used a moon clock which was effective in learning the phases. We Looking at everything I noticed that always have of the moon is light Just like Earth. We see different parts of the moon each night because the sun shines on the moon differently corresponding to the moons direction.

Making a model really helped me understand the phases of the moon I could clearly see why and where the sunlight is shining. Disadvantages of using models are that they are not always accurate and can sometimes show us a wrong representation.

Sun and Earth observations

Guiding Question: What causes the seasons? How does the tilt of Earth’s axis affect the light received by Earth as it revolves around the Sun?

Hypothesis: We believe that the tilt of the earth and the ultraviolet rays affect the the seasons and the length of the day.

Observing: When it’s winter in the northern hemisphere, the concentrated light is in in the southern hemisphere, especially a little under the equator. When it’s summer in the Northern hemisphere, The most concentrated light is just above, the equator, But also the whole of Northern hemisphere.

Observing: During the winter, in the Northern hemisphere, half way between the equator and the north pole, much less light is received during winter since the concentrated light is in the southern hemisphere. When it’s summer in the northern, most of the concentrated light is half way between the equator and the North pole.

Inferring: If the squares projected on the ball from the acetate become larger, the amount of heat distributed lowers down and becomes colder.

Inferring: The coolest places on earth constantly, are the poles. When it’s summer in the Northern hemisphere

Predicting: We predict that when the toothpick is at its longest time of the year, it will be Summer, and the shortest time will be Winter. This is similar to the Summer and Winter solstices.

Drawing Conclusion: It all depends, when the square, used from the torch, gets closer to the Earth, it gets colder, and depending on how close you put the square to the Earth, it will get even colder. On the other hand, when the squares are farther away from the Earth, it get warmer, then slowly, hotter.

Unit Reflection

Waves are very important to both people and the world around us. They very much affect the societal well being. Modern day society couldn't live without waves we use then for so many things we don't even realize. A good example is the cell phone it wouldn't function without radio waves, but people don't realize that, it's just a tool they use everyday. Another example is the TV. Waves make damage but they bring us much more good, they can be used as tools or even medicine to cure cancer. So I conclude that we should continue using waves and even expand there uses, because they really bring more good to society then bad.

I learned a lot about waves in this unit, all there uses, Now I really notice that waves are all around us and that there the steam engine for the modern world. When i first thought of waves i thought of sea and ocean waves we see when we go to the beach.

I liked doing experiments, through them I really noticed that waves are all around us and all there uses in the modern world.

For next years 7th graders i would put more experiments because through my experience there the most helpful.

Food Irradiation

The last few classes, we studied food irradiation. What are some benefits and some disadvantages of it. We researched the topic and then had a debate in groups.

These are some pros we found

Irradiation can kill or substantially reduce the number of potentially dangerous organisms in foods. Estimates range for 90 to 99.9%.

Irradiation can kill insects and pests infesting foods such as grains and flours without leaving chemical residues.

Irradiation can be used to sterilize food for immune-compromised individuals such as AIDS patients.

Irradiation has been deemed safe by various governmental agencies.

Proponents of irradiation compare the changes in food caused by irradiation (called radiolytic products) to products created by other processes such as cooking or freeze-drying.

Irradiation delays ripening and sprouting so food can be stored longe

And these are some of the cons we found:

environmental destruction

costs a lot!

problems have been discovered in animals that ate irradiated food (premature death, rare form of cancer, liver damage, vitamin deficiencies)

masks and encourages filthy conditions in slaughterhouses (kills bacteria but does nothing for feces, urine, pus, and vomit)

doesnt kill the pathogen that causes mad cow disease, either

destroys vitamins (80 % vitamin a in eggs, etc.)

can change the flavor, odor and texture of food (pork turns red, beef smells like wet dog, fruits and veggies become mushy, eggs can lose their color and become runny

disrupts the chemical composition of everything in its path

forces farmers and ranchers out of business, even WORSE for our economy

high energy gamma rays create free radicals in the cells they penetrate which is implicated in heart disease

new compounds are formed radiolytic products not sure whether they are toxic or not

food poisoning bacteria could become resistant to irradiation over time just like with antibiotics

kills good bacteria

Our group made a proposal we all agreed on this is it:

Dear FDA,

The students of ISB’s proposal to you is that irradiation must be proven to be healthier, without hazard and, in the long run, better for our economy before irradiated food is allowed to be produced and put into stores all around the world. It must also be clear that the food the customers are buying irradiated food.