The answer is no moons<span> at all. That's right, </span>Venus<span> (and the planet Mercury) are the only two planets that don't </span>have<span>a single natural </span>moon<span> orbiting them. Figuring out why is one question keeping astronomers busy as they study the Solar System.</span>
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:
Explanation:
solid
This type of matter is know as solid. Also, it is known that solid substances have definite shape and volume. Thus, we can conclude that a substance with a definite shape and volume is a solid phase of matter.
Answer:
A-500 N
Explanation:
The computation of the tension in the chain is shown below
As we know that
F = ma
where
F denotes force
m denotes mass = 7
And, a denotes acceleration
Now for the acceleration we have to do the following calculations
The speed (v) of the hammer is
v = Angular speed × radius
where,
Angular seed = 2 × π ÷ Time Period
So, v = 2 × π × r ÷ P
v = 2 × 3.14 × 1.8 ÷ 1
= 11.304 m/s
Now
a = v^2 ÷ r
= 70.98912 m/s^2
Now the tension is
T = F = m × a
= 7 × 70.98912
= 496.92384 N
= 500 N
Strange as it may seem, I don't think ANY of those choices will work. Anybody else ?
