Answer:
the first one looks like a spiral galixy
the 2nd one looks like a lenticular galixy ?? (im pretty sure but not 100%)
the 3rd one looks like a elliptical galixy
Explanation:
The problem should only have one part to it, but this one has two.
Before I can do the mass/energy conversion, I have to go and
look up the proton mass for myself ... go out and collect the straw
to make my bricks, as it were. As if the fabulous bounty of 7 points
makes it worth it. They make us do everything around here.
OK. In my Physics book⁽¹⁾, the proton rest mass is
1.67 x 10⁻²⁷ kg.
The formula that relates mass to the equivalent energy is
E = m c² .
The method of applying the formula is known as "plug in what you know",
as follows:
E = (mass) x (speed of light)²
= (1.67 x 10⁻²⁷ kg) x (3 x 10⁸ m/s)²
= (1.67 X 10⁻²⁷ Kg) x (9 x 10¹⁶ m²/s²)
= (1.5 x 10⁻¹⁰) (kg-m²/s²)
= 1.5 x 10⁻¹⁰ joule .
____________________________________
⁽¹⁾ Halliday, David and Resnick, Robert, Physics , John Wiley & Sons,
Inc., 1960, inside front cover, "SELECTED PHYSICAL CONSTANTS".
Answer:
m1 = 20g (= 0.02 kg)
Mass of pistol, m2 = 2 kg
Initial velocity of the bullet (u1) and pistol (u2) = 0
Final velocity of the bullet, v1 = +150m s-1
Let v be the recoil velocity of the pistol.
Total momentum of the pistol and bullet after it is fired is
= (0.02 kg x 150 m s-1) + (2 kg x v m s-1)
= (3 + 2v) kg m s-1
Total momentum after the fire = Total momentum before the fire
3 + 2v = 0
→v = -1.5 m/s
