The escape velocity from Earth does not depend on MCQ with Answer and Explanation

Explanation:
U ∝ V². If V' = 2V, U' = 4U. Energy scales with square of voltage. Memory aid: 'Capacitor energy: U ∝ V²; double voltage ⇒ quadruple energy'. Electrostatics proportionality frequently tested in competitive exams.

Explanation:
Vertical motion is independent of horizontal. t = √(2h/g). Mass doesn't affect. Horizontal velocity affects range, not time of fall. Projectile motion independence of perpendicular components.

Explanation:
R ∝ L/A. New L'=2L, A'=A/2 => R' = ρ(2L)/(A/2) = 4ρL/A = 4R. Alternatively, volume constant? Not given, here both changed independently. So 4R.