T1=1 hour
⇒ω1==2πrad/hour
T2=8 hours
⇒ω2=4πrad/hour
R1=2×103km
As T2∝R3
⇒(R1R2)3=(T1T2)2⇒R1R2=(81)2/3=4⇒R=8×103km
V1=ω1R1=4π×103km/h
V1=ω2R2=2π×103km/h
Relative ω=R2−R1V1−V2=6×1032π×103=3πrad/hour
x=3
Two satellites revolve around a planet in coplanar circular orbits in anticlockwise direction. Their period of revolutions are 1 hour and 8 hours respectively. The radius of the orbit of nearer satellite is 2×103km. The angular speed of the farther satellite as observed from the nearer satellite at the instant when both the satellites are closest is xπradh−1, where x is _______.
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