Quiz 1
1. Which is the closest planet to the Sun?
Ans: Mercury
2. What is the name of the 2nd biggest planet in our solar system?
Ans: Saturn
3. Which is the hottest planet in our solar system?
Ans: Venus
4. Which planet is famous for its big red spot on it?
Ans: Jupiter
5. Which planet is famous for the beautiful rings that surround it?
Ans: Saturn
6. Who was the first person to walk on the moon?
Ans: Neil Armstrong
7. What planet is known as the red planet?
Ans: Mars
8. What is the name of NASA’s most famous space telescope?
Ans: Hubble's Space Telescope
9. What is the name of the first satellite sent into space?
Ans: Sputnik
10. Ganymede is a moon of which planet?
Ans: Jupiter
11. What is the name of Saturn’s largest moon?
Ans: Titan
12. Olympus Mons is a large volcanic mountain on which planet?
Ans: Mars
13. What type of galaxy is the Milky Way?
Ans: Spiral
Tell me what is blackhole in the space ? I wanna know
ReplyDeleteA black hole is a region of spacetime from which gravity prevents anything, including light, from escaping. The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that marks the point of no return. The hole is called "black" because it absorbs all the light that hits the horizon, reflecting nothing, just like a perfect black body in thermodynamics. Quantum field theory in curved spacetime predicts that event horizons emit radiation like a black body with a finite temperature. This temperature is inversely proportional to the mass of the black hole, making it difficult to observe this radiation for black holes of stellar mass or greater.
DeleteIf the thing can't return from there then where is it go ?
ReplyDeleteWhat Is a Black Hole?
ReplyDeleteSimply put, a black hole is a region of
space that is so incredibly dense that
not even light can escape from the
surface. However, it is this fact that
often leads to miss-understanding.
Black holes, strictly speaking, don't
have any greater gravitational reach
than any other star of the same
mass. If our Sun suddenly became a
black hole of the same mass the rest
of the objects, including Earth, would
be unaffected gravitationally. The
Earth would remain in its current
orbit, as would the rest of the
planets. (Of course other things
would be affected, such as the
amount of light and heat that Earth
received. So we would still be in
trouble, but we wouldn't get sucked
into the black hole.)
There is a region of space
surrounding the black hole from
where light can not escape, hence
the name. The boundary of this
region is known as the event
horizon, and it is defined as the
point where the escape velocity
from the gravitational field is equal
to the speed of light. The calculation
of the radial distance to this
boundary can become quite
complicated when the black hole is
rotating and/or is charged.
For the simplest case (a non-
rotating, charge neutral black hole),
the entire mass of the black hole
would be contained within the event
horizon (a necessary requirement
for all black holes). The event horizon
radius (Rs) would then be defined as
Rs = 2GM/c2.
Latif.