Problema Solution
light weight travels at a speed of 186,000 miles per second. find a model for the distance d light travels after h hours. given that the distance to the nearest star (Alpha Centauri) outside our solar system is 23.5 trillion miles away, how many years does it take for light emanating from earth to reach the star?
Answer provided by our tutors
we are given the speed of light in miles per second and need to express it in hours... presumably miles per hour, so that the distance of travel in miles, 'd', can be calculated when the time in hours, 't' is known
(miles/second) * (3600seconds/hour) = miles/hour
so we multiply miles/second times 3600 to obtain miles/hour
distance = speed * time, so our formula is:
d = 186000 * 3600 * t = 6.696*10^8 t
given that d=23.5 * 10^12, calculate 't'
23.5 * 10^12 = 6.696*10^8 t
t = 23.5 * 10^12 / 6.696*10^8
t = 23.5/6.696 * 10^4
t = 3.509 * 10^4 hours
we take a year with 365 days as the measure of a year:
365 days * 24 hours/day = 8760 hours
our time, 't', in years:
t = 3.509 * 10^4 / 8760 = 4.005
it would take light emanating from earth approximately 4 years to reach the nearest star