Difficulty: Easy
Correct Answer: True
Explanation:
Introduction / Context:
SHM is a foundational motion model for oscillators (springs, pendulums for small angles, masses). It underpins vibration theory, acoustics, and many control-system approximations near equilibrium.
Given Data / Assumptions:
Concept / Approach:
The defining differential equation is a = d^2x/dt^2 = −ω^2 x, showing acceleration proportional to displacement and directed toward x = 0 (negative sign). Thus, acceleration always points toward the mean position, reversing direction as the particle passes through equilibrium.
Step-by-Step Reasoning:
Verification / Alternative check:
Energy view: total energy E = (1/2)k x^2 + (1/2)m v^2 remains constant; slope of potential pulls the mass back toward x = 0, consistent with acceleration direction.
Why Other Options Are Wrong:
Saying “False” would contradict the SHM definition; without the “proportional to displacement” part, the motion may not be strictly SHM, but the directionality statement is still correct for SHM.
Common Pitfalls:
Forgetting proportionality as well as direction; assuming large-angle pendulum motion is perfectly SHM (it is only approximate).
Final Answer:
True.
Discussion & Comments