so the 1st on is the one on the left, middle is right and the 3rd one is the right one
B. Ptolemy believed that the earth was the center of the universe
Answer : The wavelength of photon is, 
Explanation : Given,
Energy of photon = 
Formula used :
As, 
So, 
where,
= frequency of photon
h = Planck's constant = 
= wavelength of photon = ?
c = speed of light = 
Now put all the given values in the above formula, we get:
Conversion used : 
Therefore, the wavelength of photon is,
A point charge is located at the origin of a coordinate system. A positive charge is brought in from infinity to a point. The charges are at distance for given electrical potential energy is 3.34 x 10⁷ m.
<h3>What is electric potential energy?</h3>
The electric potential energy is the work done by a test charge to bring it from infinity to a particular location.
The electric potential energy is given by the relation,
V = kQ/r
where k = 9 x 10⁹ J.m/C ,Q = 3 x 10⁻⁹ C, V =8.09 × 10⁻⁷ J.
Substitute the values into the expression to get the distance between the charges.
8.09 × 10⁻⁷ = 9 x 10⁹ x 3 x 10⁻⁹ / r
r =3.34 x 10⁷ m
Thus, the distance between the charges will be 3.34 x 10⁷ m.
Learn more about electric potential energy.
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Answer:
m=ρV
V=4/3 * pi * r3
V=1.3 * 3.14 * 3.9^3
V=242.14 cm^3
m=7.58 * 242.14
m=1.8 kG
Explanation:
1. We calculate volume for sphere.
2. Then we calculate mass of sphere.
