SHM vs Periodic vs Non-Periodic Motion | NCERT Oscillations Ex 14.4 | JEE NEET

How do you decide whether a motion is SHM, periodic but not SHM, or non-periodic?
NCERT Class 11 Oscillations Exercise 14.4 gives the exact rule.
This video builds a clear decision method required for JEE & NEET.
NCERT Class 11 Physics | Oscillations — Exercise 14.4

This question teaches the MOST IMPORTANT classification rule of oscillatory motion.

Based on the displacement equation, we learn:

1️⃣ When is motion Simple Harmonic (SHM)?
✔ Displacement is a single sine or cosine function
✔ Only one fixed frequency
✔ Acceleration ∝ displacement

2️⃣ When is motion Periodic but NOT SHM?
✔ Motion repeats after a fixed time
✔ Displacement is NOT a single sine/cosine
✔ Examples include:
• Powers of sine/cosine
• Sum of multiple harmonics

3️⃣ When is motion Non-periodic?
❌ Motion never repeats
❌ No fixed time period
✔ Examples:
• Exponential growth/decay
• Polynomial functions of time

Key ideas explained clearly:
✔ Why repetition alone does not mean SHM
✔ Why exponential and polynomial motions are non-periodic
✔ How to classify motion directly from the equation
✔ Common JEE/NEET traps students fall into

This is a must-watch video for:
• JEE Main & Advanced
• NEET Physics
• NCERT concept clarity