Heres a science challange?

Question

I need to calculate the speed at which the sun is travelling around the central bulge of the Milky Way Galaxy. Use the equation : speed = distance/time. Assume that the Sun travels in a circular path of radius 1.38 x 10^17 km, taking 225 million years for each trip around the central bulge. How do I do this?

Answer 1

Use the radius to calculate the circumference of it's orbit assuming it's circular and then divide that distance by the time it takes to orbit.

Answer 2

radius = R = 1.38 x 10^17 km
round trip = 2 x pi x R = 8.67 * 10^17 km
divide by time 2.25 x 10^8 years = 3.85 x 10^9 km / yr
divide by 365.25 = 1.055 x 10^7 km / day
divide by 24 = 440,000 km / hr, pretty damned fast.

In fact it would be about 0.0004 of the speed of light.

However, Wikipedia suggests the Sun is at a larger radius than in your question, about 2.46 x 10^17 km, which would give us 780,000 km / hr or 0.0007 of the speed of light.

Answer 3

find the circumference of the circular path. then divide by time.



C=2pi r (not to be confused with area of a circle (pi r^2))
C=2(3.14...)1.38*10^17
C=867079572390782933.816km

S=867079572390782933.816/225000000
S=3853686988.403 km/yr
S=439617.498 km/hr
S=273,178.313 mph

I dont know if thats right but I tried
p.s the speed of light is about 655,454,117.6 mph

Answer 4

use the radius to calculate the circumference: 2 x pi x r(radius)

the circumference is the distance travel so:
speed(v) = distance(circumference) / time(years)
v = 0.385 km/year

or if you need smaller units just multiply this solution by the factor needed:
to get days multiply by 365.25
to get hours multiply by 365.25 x 24
to get minutes multiply by 365.25 x 24 x 60
to get seconds multiply by 365.25 x 24 x 60 x 60

Answer 5

distance = pi(1.38 x 10^14 m)^2
time = 225,000,000 years (365 days/yr ) (24 hrs/day) (60 mins/hr) (60 sec/hr) + .25(225,000,000)(24 hrs/day) (60 mins/hr) (60 sec/hr)

use those numbers

(i used meter and second)