A Plane leaves an airport x,20.6earth and 36.8north,and flies due south a long the same longitude for 8 hours at the rate of 1000km/h to another airport y,20.6earth and 0south,the plane then flies west to another airport z for 8 hours at the same speed calculate to the nearest degree (a)the value of 0 (b)the longitude of z (take the radius of the earth to be 6400km)

Question

A Plane leaves an airport x,20.6earth and 36.8north,and flies due south a long the same longitude for 8 hours at the rate of 1000km/h to another airport y,20.6earth and 0south,the plane then flies west to another airport z for 8 hours at the same speed calculate to the nearest degree  (a)the value of 0  (b)the longitude of z   (take the radius of the earth to be 6400km)

oobleck · Answer

I assume you meant X is at 20.6E 36.8N Each degree of latitude is 111km so 8000km S makes it 36.9-72.07=35.17°S At latitude Ø, the radius of a parallel is 6400cos(Ø) km so at 35.17S, r = 5231.66 km So now 8000km W = 8000/(5231.66 * 2π) * 360 = 87.61° so the final longitude is 20.6-87.6 = 67°W