algrebra word problem-size of the milky way?

Question

speed of light is about 186,000 mi/sec. the milky way galaxy has an approx diameter of 6x10 ^17 mi. estimate the # of years it would take the light to travel across th milky way.

thanks for the help.

Answer 1

time=distance/speed,plugging in
=6*10^17/1,86000*3600*24*365.25 so many years
1.02*10^5 years

Answer 2

Speed is the change in distance over a period of time, or distance divided by time.

Speed (s) = 186000 mi/sec
Distance (d) = 6x10^17 mi

Time (t) = d/s = (6x10^17 mi)/(186000 mi/sec)
t= 1.116x10^23 sec

Now convert seconds to years

(1.116x10^23 s)(1hr/3600s)(1day/24hr)(1yr/365 days)

t= 3.54x10^15 years

Answer 3

... that is very simple. So I won't do it for you mathematically.

I will give you a couple of hints.

You have your speed in mi/sec...

You have a distance in mi...

There is one operation you must do to find out how many seconds it will take you to get across the galaxy.

Once you have the seconds... simply convert that to years. Remember, 60 sec/min, 60 min/hr, 24 hr/day, 365 day/yr.