How far away is a RR Lyrae variable star if it has a period of 0.5 days and a brightness of 2.3 x 10^-11 W/m^2?

The answer is d =10^6.43 Mpc

Explanation:

Solution

To calculate the absolute magnitude of the star, we apply or use the relation with the period

Mv = - [ 2.76 (log₁₀ (P) - 1.0)] -4.16

Here P =+ 0.5 days

Mv = - 0.569

To calculate m, we have the following relation given below:

Mₓ = - 2.5 Log₁₀ (Fₓ/Fₓ,0)

Fₓ,0 = 1 w/m² (This is assumed)

Fₓ = 2.3 * 10^-11 W/m^2 (Given)

Thus

Mₓ = - 2.5 Log₁₀ (2.3 * 10^ ⁻11

Mₓ = 26.595

Now, applying the formula we have the following given below:

d = ₁₀ ( Mₓ -Mv + 5)/5

d =₁₀ (26.595 - 0.569 +5)/5

d =10^6.43 Mpc

okay i have so many questions. but the big one here is: um wt..f is this mess? ?

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.