The escape velocity from Earth's surface is approximately
A{'text': '1 km/s', 'label': 'A'}
B{'text': '11.2 km/s', 'label': 'B'}
C{'text': '30 km/s', 'label': 'C'}
D{'text': '3 × 10⁸ m/s', 'label': 'D'}
Answer & Solution
Correct answer: B. {'text': '11.2 km/s', 'label': 'B'}
1. Escape velocity is the minimum speed needed to escape Earth's gravity from its surface.
2. Formula: v_esc = √(2 g R) = √(2 G M / R).
3. Evaluating for Earth gives about 11.2 km/s.
4. It does not depend on the mass of the escaping object.
_Source: NCERT Class 11 Physics, Ch 7 "Gravitation", §7.7_
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