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What is the so called cosmic reionization process

What is the so called cosmic reionization process?

Problem B.1: Space Cannon (6 Points)

Scientists are developing a new space cannon to shoot objects from the surface of the Earth directly into a low orbit around the Earth. For testing purposes, a projectile is fired with an initial

velocity of 2.8 km/s vertically into the sky.

Calculate the height that the projectile reaches, ...

(a) assuming a constant gravitational deceleration of 9.81 m/s^2

.

(b) considering the change of the gravitational force with height.

Note: Neglect the air resistance for this problem. Use 6.67×10−11 m^3kg−1

s^−2

for the gravitational

constant, 6371 km for the Earth’s radius, and 5.97 × 1024 kg for the Earth’s mass.

(a) Explain briefly the following terms used in the text above: (i) stationary flow (ii) polytropic gas (iii) specific enthalpy (b) Show with the Rankine-Hugoniot conditions that the change in specific enthalpy is given by: Ah= P2P 2 The general form of Bernoulli's law is fulfilled on both sides of the shock separately: 2 ++h=0 where is the gravitational potential and b a constant. (c) Assuming that the gravitational potential is the same on both sides, determine how the con- stant bchanges at the shock front. (d) Explain whether Bernoulli's law can be applied across shock fronts.

(c) Is the NGC 4440 galaxy observable from the Calar Alto Observatory?

The object NGC 4440 is a galaxy located in the Virgo Cluster at the following equatorial coordinates (J2000): 12h 27m 53.6s (right ascension), 12◦17’ 36’’ (declination). The Calar Alto Observatory is located in Spain at the geographical coordinates 37.23◦N and 2.55◦W.

1. Why are massive stars important for the development of the universe?

What is the so called cosmic reionization process?

How does the shape of the Milky Way look like for the astronauts in the fast-moving spaceship? To answer this question, apply the Lorentz transformation matrix on the circular

shape to get the vectors (ct'; x'; y'; z') of the shape from the perspective of the moving spaceship

Telescopes are an essential tool for astronomers to study the universe. You plan to build your own telescope that can resolve the great red spot on the surface of Jupiter at a wavelength of 600 nm. The farthest distance between Earth and Jupiter is 968 × 10^6 km and the great red spot has currently a diameter of 16 500 km.

(a) Use the Rayleigh criterion to determine the diameter of the lens' aperture of your telescope that is needed to resolve the great red spot on Jupiter.

Impacts have formed many craters on the moon's surface. You would like to study some of the craters with your telescope. The distance between Moon and Earth is 384 400 km.

(b) What is the smallest possible size of the craters that your telescope can resolve?

Please Solve this problem for me.

The general form of Bernoulli’s law is fulfilled on both sides of the shock separately:

v

2

2

+ Φ + h = b

where Φ is the gravitational potential and b a constant.

(a) Assuming that the gravitational potential is the same on both sides, determine how the con￾stant b changes at the shock front.

(b) Explain whether Bernoulli’s law can be applied across shock fronts.