Chapter 8: Gravitation
• F = GMm/r²
• g = GM/R²
• vescape = √(2gR)
• vorbital = √(gR)
Q1. Find the escape velocity from Earth. (R = 6400 km, g = 9.8 m/s²)
Solutionve = √(2gR) = √(2 × 9.8 × 6.4 × 10⁴)
= √(125440) ≈ 11.2 km/s
Q2. Find the weight of a 70 kg person on the Moon. (gMoon = gEarth/6)
SolutionW = 70 × 9.8/6 = 686/6 ≈ 114.3 N