Answer:
1.
Astronomers define star brightness in terms of apparent magnitude — how bright the star appears from Earth — and absolute magnitude — how bright the star appears at a standard distance of 32.6 light-years.
2.
Sirius, also known as the Dog Star or Sirius A, is the brightest star in Earth's night sky. The name means "glowing" in Greek — a fitting description, as only a few planets, the full moon and the International Space Station outshine this star.
Answer:
The percentage of mass recover from recrystallization = 24.69 %
Explanation:
Given that
Initial mass of crude acetanilide = 166 gm
The mass after recrystallization = 125 gm
The mass recover from recrystallization= 166 - 125 gm
The mass recover from recrystallization= 41 gm
The percentage of mass recover from recrystallization can be find as
The percentage of mass recover from recrystallization = 24.69 %
The pressure at the depth h in the ocean is given by (Stevin's law)
where
is the atmospheric pressure
and
is the pressure exerted by the column of water of height h=4267 m, with
being the water density and
.
Substituting, we find
We want to convert this into atmospheres: we know that 1 atm corresponds to the atmospheric pressure at sea level, so
, therefore we just need to divide by this number:
(a) The velocity of the first ball before the collision with the second ball is 11.18 m/s.
(b) The final velocity of the two balls after the collision is determined as 5.59 m/s.
<h3>
Speed of the block when pushed by the spring</h3>
The speed of the block when pushed by the spring is calculated as follows;
K.E = Ux
¹/₂mv² = ¹/₂kx²
mv² = kx²
v² = kx²/m
v² = (25 x 0.5²)/0.05
v² = 125
v = 11.18 m/s
<h3>Final velocity of the two balls after the collision</h3>
The velocity of the two balls after the collision is calculated as follows;
Pi = Pf
where;
- Pi is initial momentum
- Pf is final momentum
m1u1 + m2u2 = v(m1 + m2)
0.05(11.18) + 0.05(0) = v(0.05 + 0.05)
0.559 = 0.1v
v = 5.59 m/s
Learn more about velocity here: brainly.com/question/4931057
#SPJ1