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:
2,800 n
Explanation:
hope this helps, have a nice day/night! :D
Answer:
71 rpm
Explanation:
Given that:
Angular momentum (L) = 0.26
Diameter = 25cm = 0.25 cm
Radius, r = (d/2) = 0.125m
Mass = 5.6 kg
Moment of inertia (I) = 2mr² / 5
I = (2 * 5.6 * 0.125^2) / 5
= 0.175
= 0.175 / 5
= 0.035 kgm²
Angular speed (w) ;
w = L / I
w = 0.26 / 0.035
= 7.4285714
= 7.429 rad/s
w = (7.429 * 60/2π)
w = 445.74 / 2π rpm
w = 70.941724
Angular speed = 70.94 rpm
= 71 rpm
Explanation :
(1) Big bang : (1) The most accepted theory on the origin of the universe.
This theory shows the expanding of the universe from high density and high-temperature states.
(2) Steady state : (3) All is the same and will always stay the same.
Steady state means that the properties of any system remain the same always.
(3) Oscillating universe : (4) Agrees with the big bang theory but insists the universe expanded much quicker.
Oscillating universe theory is the result of big bang theory.
(4) Inflation Choices : (2) it's like an inflating and deflating balloon that never stops.
In cosmology, cosmic inflation or deflation is just the expanding and contraction of the universe.
So, the statements and the choices are related as:
(1)-(1)
(2)- (3)
(3)-(4)
(4)-(2)
Answer:
Fc = 19.2 N
Explanation:
In this case, the force of the Honda over the rock, is a centripetal force. Then, you have:
m: mass of the rock = 600g = 0.6 kg
v: tangential velocity of the Honda = 4m/s
r: radius of the Honda = 50cm = 0.5m
You replace the values of m, r and v in the equation for Fc:
hence, the force has a magnitude of 19.2 N
If the rock would have more mass the centripetal force would be higher
