The radius of Earth at the equator is approximately 4000 miles.

Suppose a jet flies once around Earth at a speed of 5000 miles an
hour relative to Earth. If the flight path is a negligible height
above the equater, then among the following choices, what is the
best estimate of the number of hours of flight?
(a) 8
(b) 25
(c) 50
(d) 75
(e) 100
I'am more than positive that the answer is A. Just double checking. Thanks.

1 answer

Is the Jet flying East, over the poles, or West?

The Earth is moving East all the time. So if flying East, the plane has to fly once around the globe, but the globe has turned. How far did it turn? appx 1000mph*time

How far did the plane fly? 2*4000*PI+ 1000t

d=rt
8000PI+1000t=(5000-1000)t
the ( ) converts air speed to real.
t= 8.3 hrs

Now if the planes flies polar, or west, the answer is different.