Seward, Alaska is 180 degrees due west of St. Petersburg, Russia. Both cities are 60

Question

degrees north of the equator. Calculate the distance from St. Petersburg to Seward, assuming
(a)we travel along the circle of latitude;
(b)we travel along the circle that passes over the North Pole.
Thank you

Answer 1

the Earth radius at 60º N latitude is 6362 km

(a) the radius of the circle of latitude is ... 6362 cos(60º) km
... the distance is π times the radius

(b) the distance is ... (60/360) * 2 π * 6362 km