Answer:
1. Luminosity
2.Apparent brightness
Explanation:
There are two factors on which brightness of star appear to be in the sky
The two factors are
1. Luminosity
2.Apparent brightness
1.Luminosity :It is defined as the total energy emitted by the object in a given time.Luminosity vary with the distance of observer from the star.Luminosity is a intrinsic property which depends on the fundamental chemical composition and structure of the material.Luminosity is depends on the size of star.Lager the star luminosity will be more.
2.Apparent brightness: It is defined as how bright a star appears from an observer on the earth and the amount of starlight reaching the earth.if the distance is large then the brightness decreases.When the distance of star from us small then the brightness of star increases.Distance is inversely proportional to brightness of the star.
V = [4/3]π r^3 => [dV / dr ] = 4π r^2
[dV/dt] = [dV/dr] * [dr/dt]
[dV/dt] = [4π r^2] * [ dr/ dt]
r = 60 mm, [dr / dt] = 4 mm/s
[dV / dt ] = [4π(60mm)^2] * 4mm/s = 180,955.7 mm/s
Answer:
Not possible
Explanation:
Unless there's some extra external force to keep both particles at rest after the collision, the momentum must be conserved before and after the collision.
So before the collision, 1 particle is at rest, 1 not -> total momentum is non-zero
After the collision, both particles are at rest -> total momentum is zero which is different from before.
Therefore this is not possible.
... the density of the liquid
... the volume of the submerged object
Answer:
Time taken to reach final velocity = 5.5 second
Explanation:
Given:
Initial velocity (Starting from rest)(u) = 0 m/s
Acceleration of ball (a) = 1 m/s²
Final velocity (v) = 5.5 m/s
Find:
Time taken to reach final velocity
Computation:
Using first equation of motion;
v = u + at
where,
v = final velocity
u = initial velocity
a = acceleration
t = time taken
5.5 = 0 + (1)(t)
5.5 = t
Time taken to reach final velocity = 5.5 second
