Answer:
The minimum speed required is 5.7395km/s.
Explanation:
To escape earth, the kinetic energy of the asteroid must be greater or equal to its gravitational potential energy:
or
where 
is the mass of the asteroid, 
is its distance form earth's center, 
is the mass of the earth, and 
is the gravitational constant.
Solving for 
we get:
putting in numerical values gives
in kilometers this is
Hence, the minimum speed required is 5.7395km/s.
Answer:
a) false
b) True
c) True
d) False
e) False
Explanation:
a) False
For a diverging lens, the focal length is negative while it is positive for a converging lens
b) True
Image distances for virtual images are always negative and it also forms on the the same side of the lens as the object and is enlarged
c) True
d) False
For a diverging lens, the focal length is negative while it is positive for a converging lens
e) False
Image distances for virtual images are always negative and it also forms on the the same side of the lens as the object and is enlarged
Answer:
6.667 m/s
Explanation:
500 meters = 75 seconds
500 meters / 75 seconds = 6.667 m/s
Answer:
It is very rare to see a solar eclipse from your home, because the Earth, Sun, and the moon need to align just right. Not everyone in the world can view a solar eclipse, only some area can. A solar eclipse is where the moon blocks out the sun. If you think about it: Let's say you live in Florida, U.S.A. You may see the moon coming in front of the sun, but if you lived in California or sumthin', the moon and the sun wouldn't be aligned to form a solar eclipse. It all depends on location... so it is rare to see one.
Answer:
First law of thermodynamic state that energy is always conserved, in other word, energy cannot be created or destroyed.
This means that energy can only transfer from one source to another.
For example, the electricity we used to power our phone didn't come from nowhere.
We charge our phone using the energy from the electricity from the outlet.
The outlet gets its energy from the power plant, who generated that energy from burning coal.
The coal they burned got their energy while they were alive as plants.
The plants got their energy from the sun.
The sun got its energy from other cosmic stuff and so on...
My point is that the energy we use will always cycle around. It doesn't come from thin air and it doesn't disappear into thin air either. This help keeps things balance because if energy is created out of thin air then the earth might just blow up. If energy gets erased into thin air then there'll be nothing to fuel life.
