Question

The Sun is orbiting around the entire galaxy such that it completes a full orbit once every 2 × 10 8 years. Using careful measurements of phenomena known as masers, we have acurately measured the distance to the center of the galaxy to be approximately 8 kpc (kiloparsecs). This is enough information to calculate our orbital speed. (Assume that the path the Sun takes is a circle which has a circumference of C = 2 ? R .) Report your answer in kilometers per second.

Answer 1

245.75 km/sec

Step-by-step explanation:

We have given distance as 8 kilo parsec

We know that
`1\ kilo\ parsec=3.086* 10^(16)km`

So 8 kilo parsec =8×3.086×
`10^(16)` km=2.469×
`10^(17)` km

We know that circumference = 2×Π×R

So circumference =2×3.14×2.469×
`10^(17)` = 15.50×
`10^(17)` km

We know that
`speed =(distance)/(time)`

We have given time =2×
`10^8` year

=2
`10^8`×365×24×60×60 sec

So
`speed=(15.5* 10^(17))/(6.30* 10^(15))=245.75\ km/sec`