math
If a satellite completes an orbit 820 miles above the earth in 11 hours at a velocity of 22,000 mph, how long would it take a satellite to complete an orbit if it is at 1400 miles above the earth at a velocity of 36,000 mph? (Use 36,000 miles as the radius of the earth. )

The answer should be 7.54 hours. What is the formula I need to get this answer?
posted by vera

The formula that will clear up your problem is
......Vc = sqrt(µ/r)
where Vc = the velocity required to keep a body in a circular orbit, in feet/sec., r = the orbital radius in feet and µ = the Earth's gravitational constant or 1.407974x10^16 ft^3/sec^2.
The numbers you offer are inconsistent and unreal. Also, the radius of the earth is 3963 miles or 20,924,640 feet.
The real circular velocity for an orbit of 820 miles altitude is
Vc = sqrt(1.407974x10^16/(3963+820)5280
Vc = 23,612 fps or 16,099 mph.
The orbital period is therefore
Tc = (3963+820)5280(2)3.14/23,612 hr
Tc = 112 min.
The orbital period may also be derived from
Tc = 2(Pi)sqrt(r^3/µ)
Tc = 6.28sqrt(25,254,240^3/1.407974x10^16)
Tc = 6720 sec. or 1.866 hr or 112 min.
For the 1400 mile altitude,
Tc = 15,203mph and Tc = 132.98 min.
Tc(1400)/Tc(840) = r(1400)^(3/2)/r(840)^(3/2)posted by tchrwill

Lucy have 211 coins how much she have
posted by jaida
Respond to this Question
Similar Questions

Math WORD PROBLEM
The time in hours it takes a satellite to complete an orbit around the earth varies directly as the radius of the orbit (from the center of the earth) and inversely as the orbital velocity. If a satellite completes an orbit 860 
Math
When a satellite is h kilometres above Earth,the time,t,in minutes,to complete one orbit is given by the formula t=Root of (6370+h)^3/6024 a) A telecommunications satellite is placed 30 km above Earth. How long does it take the 
Physics
I really need you answered this to my email. It's very important, for this may decide my result in the school exams, and I really need a good mark. Unfortunately, Portuguese system of education is full of problems... The question 
Geometry
A satellite in a nearly circular orbit is 2000 km above Earth's surface. The radius of Earth is approximately 6400 km. If the satellite completes its orbit in 112 hours, calculate the speed of the satellite in kilometers per hour. 
Physics
An earth satellite moves in a circular orbit with an orbital speed of 5800 m/s. Find the time (expressed in seconds) of one revolution of the satellite. Find the radial acceleration of the satellite in its orbit. I think we need 
geometry
A satellite in a nearly circular orbit is 2000 km above Earth's surface. The radius of Earth is approximately 6400 km. If the satellite completes its orbit in 12 hours, calculate the speed of the satellite in kilometers per 
Algebra
A satellite is in orbit around the earth, traveling at a rate of 85.4 minutes per orbit. a space shuttle enters the same orbit, traveling at a rate of 93.6 minutes per orbit. the shuttle is .25 orbits behind the satellite, 
physics
The mass of the Earth is 5.972kg, and the radius of Earth is 6, 371 km. A 750 kg satellite orbits 35, 800 km above Earth in a perfectly circular orbit. 1. If the gravitational force is the centripetal force keeping the satellite 
Math
a satellite traveling in a circular orbit 2000 kilometers above the earth completes one orbit every 3 hours. assume the earth is a sphere and its radius is 6400 kilometers. find the angular velocity of the satellite 
Math
a satellite traveling in a circular orbit 2000 kilometers above the earth completes one orbit every 3 hours. assume the earth is a sphere and its radius is 6400 kilometers. find the angular velocity of the satellite