Verified Solution • 2025–26 Session moderate

Q7.19: NCERT Physics - Part 1 GRAVITATION 7.19 Solution: A satellite orbits the earth at a height of 400 km above the…

A satellite orbits the earth at a height of 400 km above the surface. How much energy must be expended to rocket the satellite out of the earth's gravitational influence? Mass of the satellite =200= 200 kg; mass of the earth =6.0×1024= 6.0 \times 10^{24} kg; radius of the earth =6.4×106= 6.4 \times 10^6 m; G=6.67×10−11G = 6.67 \times 10^{-11} N m_ kg__.

Step-by-Step Verified Solution

**Answer:** 5.9×1095.9 \times 10^9 J **Step-by-Step Explanation:** Total energy of satellite in orbit:
E=−GMm2(R+h)=−(6.67×10−11)(6×1024)(200)2(6.4×106+4×105)=−5.9×109 JE = -\frac{GMm}{2(R+h)} = -\frac{(6.67 \times 10^{-11})(6 \times 10^{24})(200)}{2(6.4 \times 10^6 + 4 \times 10^5)} = -5.9 \times 10^9 \text{ J}
Energy required to remove it to infinity = −E=5.9×109 J-E = 5.9 \times 10^9 \text{ J}

All Questions in this Chapter

Q7.1 Q7.2 Q7.3 Q7.4 Q7.5 Q7.6 Q7.7 Q7.8 Q7.9 Q7.10 Q7.11 Q7.12 Q7.13 Q7.14 Q7.15 Q7.16 Q7.17 Q7.18 Q7.19 Q7.20 Q7.21

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