Atoms begin to gravitate together to form a center
Answer:
Explanation:
The energy of a photon is given by the equation 
, where h is the <em>Planck constant</em> and f the frequency of the photon. Thus, N photons of frequency f will give an energy of 
.
We also know that frequency and wavelength are related by 
, so we have 
, where c is the <em>speed of light</em>.
We will want the number of photons, so we can write
We need to know then how much energy do we have to calculate N. The equation of power is 
, so for the power we have and considering 1 second we can calculate the total energy, and then only consider the 4% of it which will produce light, or better said, the N photons, which means it will be 
.
Putting this paragraph in equations:
.
And then we can substitute everything in our equation for number of photons, in S.I. and getting the values of constants from tables:
Answer:
250N
Explanation:
Given parameters:
Time = 4s
Momentum = 1000kgm/s
Unknown:
Force = ?
Solution:
To solve this problem, we use Newton's second law of motion;
Ft = Momentum
F is the force
t is the time
So;
F x 4 = 1000kgm/s
F = 250N
Answer:
8.91 J
Explanation:
mass, m = 8.20 kg
radius, r = 0.22 m
Moment of inertia of the shell, I = 2/3 mr^2
= 2/3 x 8.2 x 0.22 x 0.22 = 0.265 kgm^2
n = 6 revolutions
Angular displacement, θ = 6 x 2 x π = 37.68 rad
angular acceleration, α = 0.890 rad/s^2
initial angular velocity, ωo = 0 rad/s
Let the final angular velocity is ω.
Use third equation of motion
ω² = ωo² + 2αθ
ω² = 0 + 2 x 0.890 x 37.68
ω = 8.2 rad/s
Kinetic energy,
K = 0.5 x 0.265 x 8.2 x 8.2
K = 8.91 J
<h2>Right answer: Comets have very elliptical orbits that usually take them far beyond the orbit of Pluto, but also take them closer to the Sun than Earth</h2>
Comets are celestial bodies constituted by ice, dust and rocks that orbit around the Sun, after having been altered by the Oort cloud; following different trajectories that can be <u>highly eccentric elliptical</u><u> </u>(periodic trajectories), parabolic or hyperbolic.
One of the main characteristics of a comet is that it travels quite fast, on its way around the Sun and has a long tail. It should be noted that the tails of comets always go in the opposite direction to the Sun (due to the radiation pressure of sunlight).
Therefore, the correct option is C.
