Spring force and potential energy of a springकमानी बल और कमानी की स्थितिज ऊर्जा
NCERT Fig 5.7 & 5.8 · interactive diagram
Parts and their functions
- Ideal spring (constant k) (आदर्श कमानी (नियतांक k)) — Massless; obeys Hooke’s law F = −kx. SI unit of k: N m⁻¹.
- Block of mass m (m द्रव्यमान का गुटका) — On a smooth surface; oscillates about x = 0.
- Displacement x (विस्थापन x) — Measured from the relaxed (unstretched) position.
- Restoring force F = −kx (प्रत्यानयन बल F = −kx) — Always towards x = 0. Work done by the spring from 0 to x: W_s = −½kx².
- Potential energy V = ½kx² (स्थितिज ऊर्जा V = ½kx²) — A parabola; same for stretch and compression. The spring force is conservative.
- Total energy E (कुल ऊर्जा E) — E = K + V = ½kxₘ² = ½mvₘ², constant (no friction).
- Turning points ±xₘ (वापसी बिंदु ±xₘ) — Here V = E and K = 0. Example 5.8: xₘ = √(2K/k) = √(2 × 1.25 × 10⁴ / 5.25 × 10³) = 2.18 m.
- Kinetic energy at x = 0 (x = 0 पर गतिज ऊर्जा) — All energy is kinetic at the centre: speed is maximum vₘ.
Original diagram drawn by Simple Learning Hub, based on NCERT Fig 5.7 & 5.8. Report a mistake