Question

Our solar system orbits the center of the Milky Way galaxy. Assuming a circular orbit 30,000 ly in radius and an orbital speed of 250 km/s, how many years does it take for one revolution? Note that this is approximate, assuming constant speed and circular orbit, but it is representative of the time for our system and local stars to make one revolution around the galaxy.

(a)1.9×10⁷years
(b)2.4×10⁷years
(c)3.6×10⁷years
(d)4.8×10⁷years

Answer 1

It takes approximately 1.9×10^7 years for one revolution of our solar system around the center of the Milky Way galaxy.

Step-by-step explanation:

To calculate the time it takes for one revolution of our solar system around the center of the Milky Way galaxy, we can use the formula:

Time = (circumference of the orbit) / (orbital speed)

The circumference of the orbit is given by 2×π×radius, where the radius is 30,000 light-years. Since the speed is given in km/s, we need to convert the distance to kilometers by multiplying it by the speed of light (9.46×1012 km/yr). Plugging in the values, we get:

Time = (2×π×30,000×9.46×1012) / (250)

Calculating this expression gives us approximately 1.9×107 years for one revolution of our solar system around the Milky Way galaxy's center.