A car accelerates from rest at 2 m/s² for 10 s, then moves with constant velocity for 10 s. Total distance covered is MCQ with Answer and Explanation

Explanation:
Resonance: X_L = X_C ⇒ they cancel ⇒ Z = R (minimum). Current maximum at resonance. Memory tip: 'Series resonance: Z_min = R; parallel: Z_max'. AC circuit concept frequently tested in competitive exams.

Explanation:
Resistance (R) of a wire is given by R = ρL/A, where ρ is resistivity, L is length, and A is cross-sectional area. If L becomes 2L and A becomes 2A, the new resistance is R' = ρ(2L)/(2A). The 2s cancel out, leaving R' = ρL/A = R. Thus, the resistance remains entirely unchanged.

Explanation:
SHM definition: acceleration a ∝ -x (displacement), i.e., a = -ω²x. This restoring acceleration causes oscillatory motion. Constant acceleration implies uniformly accelerated motion (not oscillatory). Constant velocity implies no acceleration. Memory tip: 'SHM: a = -ω²x; force F = -kx (Hooke's law)'. This conceptual question tests fundamental SHM characteristics, frequently examined in competitive exams. Always link to examples: mass-spring system, simple pendulum (small angles), LC circuits.