Light from the Sun takes 8 minutes to reach Earth. How long does it take to reach Mars?
What is the Given & Unkown(s):
8 minutes (light to reach the sun)
t=?
Approprite formula:
?
Conversion of the formula in order to determine your unknown:
?
Inserting numbers:
8 min/ 1 Au = t/ 1.52 AU
t= (8 min x 1.52 AU)/ 1 AU = 12.2 min
Units:
?
(I don't know what to put for those 3 parts)
What is the Given & Unkown(s):
8 minutes (light to reach the sun)
t=?
Approprite formula:
?
Conversion of the formula in order to determine your unknown:
?
Inserting numbers:
8 min/ 1 Au = t/ 1.52 AU
t= (8 min x 1.52 AU)/ 1 AU = 12.2 min
Units:
?
(I don't know what to put for those 3 parts)
1 Answer
Based on speed of light (300,000 km/s): ca. 12 min. 40 sec.
Based on 8 min. from Sun to Earth: ca. 12 min
Explanation:
To compute the time, we need the following data:
Speed of light in vacuum:
(More exactly 299 792 458 m/s, but for our purposes the round figure of 300 000 fits nicely)
Distance from Sun to Mars: 228 000 000 km.
(Distance from Sun to Earth:
The only two items we need, are really the speed of light and the distance it has to travel, as our calculation then becomes:
time in seconds = Distance / speed of light
=
=
If we instead base our computation on the data we have been given, i.e. that the light uses 8 min. = 480 sek. to reach the earth, we must use the ration between Earth's distance and Mars' distance to the Sun, i.e.
=