A remote-sensing satellite is in a circular orbit 0.25×10⁶ m above Earth’s surface. Given Earth radius 6.38×10⁶ m and g=9.8 m s⁻², find its orbital speed.
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A remote-sensing satellite is in a circular orbit 0.25×10⁶ m above Earth’s surface. Given Earth radius 6.38×10⁶ m and g=9.8 m s⁻², find its orbital speed.

G1 Physics · Accepted Answer

Step 1: For orbital radius r=R+h, v=√[GM/(R+h)]. At Earth’s surface GM=gR². Step 2: Thus v=√[gR²/(R+h)]=√[9.8(6.38×10⁶)²/(6.63×10⁶)]≈7.76×10³ m s⁻¹. Final answer: A — 7.76 km s⁻¹.