To determine the speed of revolution (orbital speed) of a satellite in orbit around Earth, you can use the following formula:
v=2πrTv=T2πr​
Where:

• vv is the orbital speed (in meters per second, m/s).
• rr is the radius of the orbit (in meters, m).
• TT is the time for one complete revolution (in seconds, s).

First, let’s convert the given values:

1. The time for one complete revolution, TT, is given as 85 minutes. Convert this to seconds because 1 minute = 60 seconds: T=85 minutes×60 seconds/minute=5100 secondsT=85 minutes×60 seconds/minute=5100 seconds
2. The altitude above the Earth’s surface, hh, is given as 119 km. Convert this to meters because 1 km = 1000 meters: h=119 km×1000 meters/km=119,000 metersh=119 km×1000 meters/km=119,000 meters

Now, you can calculate the orbital speed (vv) using the formula:
v=2π⋅(r+h)Tv=T2π⋅(r+h)​

• rr is the radius of the Earth, which is approximately 6,371,000 meters (mean radius).
• hh is the altitude above the Earth’s surface (converted to meters).
• TT is the time for one complete revolution (converted to seconds).

v=2π⋅(6,371,000+119,000)5100 m/sv=51002π⋅(6,371,000+119,000)​ m/s
Calculate this to find the orbital speed (in meters per second). The result will be the speed at which the satellite revolves around Earth in its orbit.