Thursday, April 7, 2011

1.33 and 1.35

Equation to find the speed of the Earth travelling round the Sun

V=2PIr
       T
V= 2PIx149,000,000
          31,557,600

V=29.66 km/s


My graph:






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1.35: Recall that solar system is part of the Milky Way galaxy
1.) What is a Glalaxy?
A large collection of billions of stars
2.) Which galaxy are we in?
Milky Way
3.) Source an image of our galaxy

4.) What type of galaxy are we in?
Spiral galaxy
5.) How many galaxies are there in the Universe?
billions










Wednesday, March 30, 2011

1.32) Explain the effects of gravitational force

The moon orbits the earth because of the _______ _______ between them

The Earth attracts the Moon, and the Moon attracts the Earth with  an ____ but ____ force

This is an example of Newton's ____ law

Planets orbit the Sun because of the _____ between the _____ and the _______

Artificial satellites orbit the Earth because of the _____ _____ between the ______ and the _____

Comets orbit the Sun because of the _______ ________ between the __________ and the ______

If the _______ _______ were removed these objects would fly away at a t_____ to the orbit path

Sunday, March 27, 2011

1.31 : understand gravitational field strength (g) and recall that it is different on other planets and the moon from that on the Earth

Questions
Answers
What does small 'g' stand for in the equation W = mg?
 gravitational field strength (g)
What is approximate value of 'g' on Earth?
 10
What is approximate value of 'g' on the Moon?
 1.6
What are the units for 'g'?
N/kg
Why is this equation useful?
 Helps you work out the weight in comparison to mass
Why is 'g' different on different planets?
 Because different planets have different masses
Which object in our solar system has the largest 'g'?
 the sun
Explain why this object has the largest 'g'
 it has the largest mass
Where on a planet is 'g' the greatest?
 the core
What happens to the value of 'g' as you go further away from a planet?
 g decreases
How does this affect your weight?
 Decreases
Find your mass on the bathroom scales and then find your weight on different planets (click this link: http://www.exploratorium.edu/ronh/weight/), take a screen shot and upload the image to your blog







The mistake on the blog: it says weight instead of mass

1.30


http://www.freemars.org/jeff/planets/Luna/Luna.htm

How was the Moon formed?
According to this theory, the Moon was created from the debris ejected by an impact of a huge object (of the size of today's Mars) on our planet, about 4.53 billion years ago, when a molten Earth was still cooling down. Hence, formation of Moon is quite intimately connected to how was the Earth created. Let us understand how was the Moon formed from collision of young Earth with this huge Mars sized object (named Theia after the Greek Goddess who gave birth to Moon Goddess Selena, in Greek Mythology).

http://www.buzzle.com/articles/how-was-the-moon-formed.html

How old is the Moon?
About four and a half billion years old

Why does the Moon only show one side to us all of the time?
The reason that one side of the moon is never visible from the Earth is because the moon spins once on its axis in precisely the same amount of time it takes to revolve around the Earth

http://www.wisegeek.com/why-does-the-same-side-of-the-moon-always-face-the-earth.htm

The Moon is slowly drifting away from us, by how much per year?
3.8 cm per year

Explain what will eventually happen to it
A consequence of the Moon being farther away is that it takes longer to orbit the Earth; the lunar month becomes longer. In the future, the maximum length of the day will be reached when the Earth rotates at the same speed that the Moon orbits. The day and the lunar month will have the exact same length, somewhere near 47 of our present 24-hour days. At this point, since the tidal bulge will not be swinging ahead of the Moon's orbit, the Moon will no longer be moving away but will remain in a stable orbit.
.
http://answers.yahoo.com/question/index?qid=20101205074136AAISsAm

How much larger is the Sun than the Moon?
416 times larger then the moon

What natural phenomenon does this ratio help to observe?

Insert a video (and source) of the answer to the question above

How far away is the Moon?
The moon is at an average distance of 238,855 miles (384,400 kilometers) away from Earth.

What was significant about the 19th March 2011 (regarding the Moon)?
It was when the moon was closest to the earth

Why is there no atmosphere on the Moon?
With all the changes going on then, the moon was pounded by radiation with its deformed atmosphere, causing it to be swept away. Although it might have had an atmosphere when it was young but spherical, the solar winds emitted by the sun were to strong for the moon's little gravity. And, the moon doesn't have hardly enough mass to have an atmosphere... those fierce solar winds and lack of a magnetosphere will wipe that atmosphere right off of it!

http://in.answers.yahoo.com/question/index?qid=20080924220450AAeYJB7

Why is the gravity on the Moon 1/6th than of Earth?
The moon is 1/4 the size of Earth, so the moon's gravity is much less than the earth's gravity, 83.3% (or 5/6) less to be exact. Finally, "weight" is a measure of the gravitational pull between two objects. So of course you would weigh much less on the moon

http://www.moonconnection.com/moon_gravity.phtml

How many people have stepped on the Moon? Who was the last?
12 people have walked on the moon. The last person to do this was a man named Harrison Schmitt

Why does the Moon orbit the Earth?
The moon orbits the earth because it is "in motion" and its inertia, coupled with the attraction of gravity, keeps it in its orbit. The same is true of the earth and sun.

http://wiki.answers.com/Q/Why_does_the_moon_orbit_the_earth_and_why_does_the_earth_orbit_the_sun


How many days does it take to orbit?
About 28 days

What effect does the Moon have on the Earth?
The moon effects the earth in two ways. Its position around the earth allows it to reflect the sun's light into our night. The moon's orbit around the earth lasts about a month giving us different levels of this light. The 'new moon' has little light to offer and the 'full moon' provides us with the best lighting. The second effect comes from the moon's gravitational pull on the earth. As the earth rotates, the moon's pull causes the world's bodies of water to experience 'high tides.' At a given time there are two high tides on earth.
The gravitational forces between the Earth and the Moon cause some interesting effects on our oceans. The tides.

yhttp://wiki.answers.com/Q/What_effects_does_the_moon_have_on_the_earth


Insert a video (and source) of the answer to the question above



How many moons are there in our solar system?
About 240 known moons in our solar system