Suppose you observe a star orbiting the galactic center at a speed of 1200 km/s in a circular orbit with a radius of 25 light-days. What would your estimate be for the mass of the object that the star is orbiting

Mass of the earth which is orbiting star will be

Explanation:

Let the mass of object which is orbiting the star is M

And mass of of star is m

Velocity of star v = 1200 km/sec

Let the distance between them is

1 light year =

Gravitational constant

So 25 light year

Gravitational force between them is given

Centripetal of star is equal to

These two forces will be equal

So mass of the earth which is orbiting star will be

i cant see the choices man

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27