"during the opening sequences of " the day the earth stood still " the alein craft orbits the earth at 6437.376 kph. If the spaceship is flying 1.25km above the surface area of the earth , a) find the distances travelled to make a single orbit of the earth . b) the time it takes to complete one of those orbits ."
You will need the Earth's radius, re, which you should look up. It is about 6400 km. Call that Re.
The radius of the orbit, from the center of the Earth, is
R = Re + 1.25 km.
(a) The circumference of the orbit is
C = 2 pi (R + Re)
(b) The time to complete an orbit is C/6437 km/h
If you get several hours for the orbiting time, the assumptions in the movie are wrong. It would actually take about 84 minutes.
At 1.25 km above the earth's surface, the spacecraft is going to bump into some low mountains. It would also burn up in the atmosphere, travelling at that speed.