T/F Questions?

Question

A couple of questions:

1. The Earth is a perfect example of an undifferentiated planetary body.
2. The Van Allen belts are long parallel trenches in the Atlantic between
the North American and Eurasian plates.
3. Free oxygen was not present in the early terrestrial atmosphere, but
became plentiful only after plant life formed.
4. The first step in the formation of the solar system was the collapse of a rotating interstellar cloud.
5. Neptune’s rings are composed of many small particles.
6. The visible surface of Neptune is covered with water ice.
7. The Roche limit is the maximum size a planet may be without being a star.
8. The atmosphere on Mars is more dense than the Earth’s but less dense than the Venereal atmosphere.

Answer 1

1. IDK

2. F - the Van Allen belt is a radiation belt around Earth, held in place by Earth's magnetic field.

3. IDK

4. T - Something (possibly a nearby supernova) disturbed the cloud (that our solar system was formed from) of dust and gas in space, creating waves, and caused it to start to collapse. As it collapsed, the cloud started to spin. Eventually the cloud grew denser and hotter in the center, which eventually led to the birth of our sun. Further out, the cloud grew thinner and gravity caused the gas and dust to start to form clumps. These formed the planets and moons of our solar system. (This is all very over-simplified).

5. T - The rings of Neptune contain much more dust-size grains than the rings of Saturn and Uranus, and the material in one of the rings is clumpy (more dense in some areas than others).

6. F - Neptune most likely has a small rocky core, but it is a gas giant composed of various "ices" (water, methane, and ammonia all in solid form) and rock, with about 15% hydrogen and a little bit of helium. It's atmosphere is composed of hydrogen and helium with a little bit of methane (this gives it its blue color).

7. F - The Roche Limit refers to how close one celestial body can orbit another celestial body without being torn apart by tidal forces.

8. F - Venus has a very thick atmosphere, much thicker than Earth's. Mars has a very thin atmosphere, much thinner than Earth's.

Answer 2

fake. the actual, inverted photograph would be at 2f from the lens and equivalent to the size of the item. a million/f = a million/do + a million/di di = a million/(a million/f - a million/do) = a million/(a million/f - a million/(2f)) = a million/(a million/(2f)) = 2f si/so = di/do = a million

Answer 3

T
T
F
F
T
F
F
T