A galaxy is a large system of stars, remnants of dead stars, dust,
interstellar gas, and dark matter, all related to each other by gravity.
Within the part of the universe that we can observe, it's estimated that
there may be as many as two trillion galaxies !
Galaxies come in all sizes. Tiny shrimp galaxies hold no more than
a few billion stars. Really big galaxies may hold 100 trillion stars. ( ! ! )
The galaxy we live in (the "Milky Way") is somewhere in the middle.
It's very hard to estimate the number of stars in it, because we can't
get outside of it and look it over. Estimates of the number of stars in
our galaxy range from 100 billion to 400 billion stars. ( ! ! ! )
Answer:
C) If an ice cube is placed into a boiling water, then it will melt in less than 2 minutes.
Explanation:
Answer:
The heat flux between the surface of the pond and the surrounding air is<em> 60 W/</em>
<em> </em>
Explanation:
Heat flux is the rate at which heat energy moves across a surface, it is the heat transferred per unit area of the surface. This can be calculated using the expression in equation 1;
q = Q/A ...............................1
since we are working with the convectional heat transfer coefficient equation 1 become;
q = h (
) ........................2
where q is the heat flux;
Q is the heat energy that will be transferred;
h is the convectional heat coefficient = 20 W/.K;
is the surface temperature = 
C 23°C + 273.15 = 296.15 K;
is the surrounding temperature = 
C = 20°C + 273.15 = 293.15 K;
The values are substituted into equation 2;
q = 20 W/.K ( 296.15 K - 293.15 K)
q = 20 W/.K ( 3 K)
q = 60 W/
Therefore the heat flux between the surface of the pond and the surrounding air is 60 W/
The correct answer is B (Inertia)
We define inertia as the resistance to change of the state of motion. That is, a body tends to remain in its state of motion or rests unless an external for acts on it. The quantity depends on the mass of the body. If the body is heavy, it requires a large force to overcome the inertia.
Answer:
73.5 N
Explanation:
W = PE = mgh = 2.5 * 9.8 * 3.0 = 73.5 N
