Average Speed?

Question

A space shuttle circles the earth 660 km above the surface in 1 hr 32 min 10 sec. If the average radius of the earth is 6370 km, find the speed of the shuttle in m/s and km/hr.

As I understand it, I need to find the circumference of the earth (C = 2(pi)r). Is the number 660 km redundant?

Thanks.

Answer 1

V = 2*pi*r/T
r = 6,370 Km + 660 Km = 7,030 Km from the center
T = 1.536 hours = 5,530 sec

V = 28,757 Km/h = 7,988 m/s

Answer 2

Course it's not reduntant, your actual radius would be the earth plus whatever distance the shuttle is above the damn thing, in this case 660 km. In which case your radius is then 7030 km (660 km above the earth plus the earth's own 6370 km).

I'll leave the rest of the problem to you as it's nothing more than simple unit conversions.

Answer 3

''Circles the earth 660 km above the surface" means it is revolving round the earth and it is not moving in a circle above the ground . Probably you are mislead by the word 'above the surface'

The words 'above the surface' are given to indicate the height from the ground and not the radius of the circle.

The radius of the circle is earth's radius + the height.

Answer 4

Without doing any math for you (I'm in bed!), you want to make sure you use 6370 plus 660 as the radius of your circle to figure out the speed of the shuttle!

Answer 5

you dont need to find the circumference of the earth, because the shuttle is not travelling along the earths surface, the 660km is not redundant because you have to find out the circumference if the radius is 6370km + 660km. because thats the distance from the earths core the to shuttle

Answer 6

youll need to find the spherical path the shuttle is going in. this means you have to add the 660 kilometers, to the radius of the earth. then find the circumference.

Answer 7

No, it isn't. You need to find the circumference of the orbit traveled by the shuttle, not the circumference of the Earth.

Think about it ☺

Doug