📚 IIT–JEE Physics Complete Learning Hub
🔹 Core Physics Libraries
- 🔁 Simple Harmonic Motion (SHM) – Complete Library (IIT–JEE Advanced)
- 🌊 Mechanical Waves – JEE Advanced Objective Library
- 🧠 IIT–JEE Physics Complete Master Library
🔹 Central Learning Platforms
📌 Structured • Exam-Oriented • IIT–JEE Advanced Focused Learning
Stage–2 | Page–10
SHM Graphs – x–t, v–t, a–t (JEE Advanced Level)
Most conceptual + multi-correct topic in SHM
Fundamental SHM Equations
x = A sin(ωt + φ)
v = Aω cos(ωt + φ)
a = −ω²x
v = Aω cos(ωt + φ)
a = −ω²x
- All SHM graphs are phase-shifted versions of each other
- Amplitude and frequency are fixed
Displacement–Time (x–t) Graph
- Pure sine or cosine wave
- Period = T
- Slope at any point = velocity
Key Points:
At mean position → slope maximum
At extreme position → slope zero
At mean position → slope maximum
At extreme position → slope zero
IIT Trap #1 – Slope Confusion
- Slope ≠ speed (it is velocity)
- Sign of slope matters
Velocity–Time (v–t) Graph
- Cosine graph if x is sine
- Phase difference of π/2 with x–t graph
Maximum velocity = Aω
Area under v–t graph = displacement
IIT Trap #2 – Area Under Curve
- Positive area ≠ total distance
- Opposite signs cancel
Distance requires absolute area
Acceleration–Time (a–t) Graph
- Also sinusoidal
- Always opposite in phase to x–t graph
a = −ω²x
When x is maximum → a is maximum (opposite sign)
When x is maximum → a is maximum (opposite sign)
Phase Relationship Summary
| Graph Pair | Phase Difference |
| x and v | π/2 |
| v and a | π/2 |
| x and a | π |
JEE Advanced Multi-Correct Logic
- Same x → same a
- Same |v| ≠ same position
- Same graph shape ≠ same phase
Time Calculation from Graphs
- Use periodicity
- Use symmetry (half / quarter cycle)
- Avoid calculus unless forced
Graph problems reward visualization, not formulas
Frequently Asked Advanced Questions
- Matching x–t with v–t graphs
- Finding acceleration from slope
- Area interpretation traps
- Counting zero crossings
Topper Strategy
- Always mark mean & extreme positions
- Note direction of motion
- Use phase shift mentally
What Comes Next?
- Stage–3: Energy Graphs in SHM
- Advanced PYQs with graphs
- Multi-body SHM systems
Stage–2 Completed ✔ You have crossed the hardest conceptual zone 🚀

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