+0

# I am having a hard time trying to solve this for my homework

0
208
1

I have encounter similar problems like this on my worksheet. I just can't set up the formula for the life of me, can someone explain this to me so I can finish my homework?

If a planet was located approximately 29 thousand light-years from the center of a galaxy and orbits that center once every 290 million years, how fast is the planet travelling around the galaxy in km/hr? If needed, use 3.0 × 108 m/s for the speed of light.

Guest Mar 20, 2017
Sort:

#1
+26547
+1

The velocity is circumference/period.

circumference = 2pi*r  where r is radius

r = 29000yr*365days/yr*24hr/day*3*108*m/sec*3600secs/hr*0.001km/m ≈ 2.744*1017km

period = 290*106yr*365days/yr*24hr/day ≈ 2.54*1012hr

velocity ≈ 2*pi*2.744*1017/(2.54*1012) km/hr ≈ 6.8*105 km/hr

.

Alan  Mar 20, 2017

### 17 Online Users

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details