Speed of light is 3×10^8m/sec. the circumference equador is 4×10^4km. if light turns around equador for 5 min, how many tours can we count?

2250 tours

Explanation:

We have the following data:

Speed of light:

Circumference of the equador:

The time in which light turns around equator:

We need to find how many tours does light do around the equator in

Let's begin by the expression of the speed, which is a relation between the traveled distance () and time:

(1)

Isolating :

(2)

(3)

(4) This is the distance light travels in 5 min.

Now we need to know to how many tours is this distance equivalent, we can know this by a Rule of three:

1 tour ---- (circumference of the equator)

? tour ----

Then:

This is the count of tours in 5 minutes.

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west