Astronomy

[nycmathguy]

College Algebra
Chapter 1/Section 2

For 159.

There 3600 seconds in one hour. There are 24 hours in one day. So, 3600 x 24 or 86,400 seconds in one day. In 365 days, there are 31,536,000 seconds.

186,000 miles/m = 1 second/(31,536,000)

Let m = miles in one light year

Is this the correct set up?

For 160

The speed of light is 3.00 x 10^(8) miles per second.

I say (distance Sun is from Earth)/(speed of light).

Is this the correct set up?

 

[MathLover1]

The speed of light is 3.00 x 10^(8) miles per second.=> incorrect
should be 3.00 x 10^(8) km/s
even 300,000 kilometers per second =186,000 miles per second

you do not mix up units of measurement

you are given: 186,000 miles per second

so,
speed s=186000(mil/s)=1.86*10^5(mil/s)

time t=1 year=3.154*10^7 seconds

distance d=st

d=1.86*10^5(mil/s)*3.154*10^7 s.....cancel seconds
d=5.86644*10^12mil

 

[MathLover1]

160.

yes time= (distance Sun is from Earth)/(speed of light)

 

[nycmathguy]

The speed of light is 3.00 x 10^(8) miles per second.=> incorrect
should be 3.00 x 10^(8) km/s
even 300,000 kilometers per second =186,000 miles per second

you do not mix up units of measurement

you are given: 186,000 miles per second

so,
speed s=186000(mil/s)=1.86*10^5(mil/s)

time t=1 year=3.154*10^7 seconds

distance d=st

d=1.86*10^5(mil/s)*3.154*10^7 s.....cancel seconds
d=5.86644*10^12mil

I knew this one was not going to be easy.

 

[nycmathguy]

160.

yes time= (distance Sun is from Earth)/(speed of light)

At least I got this set up right.