H line of Calcium spectrum is normally given as 396.9 nm
Now from a distant star we measured it as 398.1 nm
So here this change in the wavelength of distant star is due to Doppler's effect of light as per which when source of light moves towards the observer then the frequency of light received will appear different from its actual frequency
So here we can say as per Doppler's effect of light




given that






so the start is moving away with speed 9.04 * 10^5 m/s because when wavelength is more than the real wavelength then its frequency is less which mean it is moving away from the Earth
Answer: hes not a country singer if thats what your asking
Explanation:
Answer:
H₀ = 1.6 x 10⁻¹⁸ s⁻¹
Explanation:
The Hubble's Constant can be found by the following formula:

where,
H₀ = Hubble's Constant = ?
v = speed of galaxy = 30000 km/s = 3 x 10⁷ m/s
D = Distacance = 600 Mpc = (6 x 10⁸ pc)(3.086 x 10¹⁶ m/1 pc)
D = 18.52 x 10²⁴ m
Therefore,

<u>H₀ = 1.6 x 10⁻¹⁸ s⁻¹</u>
Answer:
The circumference of the Earth is 24818.58 miles
Explanation:
Analysis conceptual : The formula of the circumference is the following:
L= π*D Formula (1)
Where:
L : is the length of the circumference in miles (mi)
π : is the constant
D : is the diameter of the circumference in miles (mi)
Known data
π = 3.1416
D= 7900 miles: Diameter of the Earth
Problem development
We apply the formula 1 to calculate the circumference of the Earth (L):
L= π*7900 miles
L= 24818.58 miles
Answer:

Explanation:
Here two charges are placed at distance "d" apart
now the net value of electric field at some position between two charges will be ZERO
so we will have
electric field due to charge 1 = electric field due to charge 2

Let the position where net field is zero will lie at distance "r" from q1

now we will have

now square root both sides

now we have

so we have
