Durgam Vigyan Sansthana

Learn To Converge Your Dreams with Durgam Vigyan Sansthana Institute. Q1. A diver in a swimming pool bends his head before diving. Why? a) Increases his linear velocity b) Decreases his angular velocity c) Increases his moment of inertia d) Decreases his moment of inertia Concept: Conservation of angular momentum L = Iω = constant When the diver bends his head, his mass comes closer to the axis of rotation. Hence, moment of inertia decreases. To conserve angular momentum, angular velocity increases. Correct Answer: (d) Decreases his moment of inertia Q2. The angular momentum of a system of particles is conserved when a) No external force acts b) No external torque acts c) No external impulse acts d) Axis of rotation remains same Angular momentum changes only if external torque is applied. τ = dL/dt If external torque is zero, angular momentum remains constant. ...

Learn To Converge Your Dreams with Durgam Vigyan Sansthana Institute. 📘 Physics MCQ Test Paper 1. What is the SI unit of force? A. Joule B. Newton C. Pascal D. Watt ✔ Answer: B — Force = mass × acceleration → Newton 2. Speed of light in vacuum is approximately? A. 3 × 10⁶ m/s B. 3 × 10⁸ m/s C. 3 × 10⁵ m/s D. 3 × 10⁷ m/s ✔ Answer: B — Universal constant 3. Which law explains action and reaction? A. First Law B. Second Law C. Third Law D. Law of Gravitation ✔ Answer: C — Newton’s Third Law 4. Unit of electric current? A. Volt B. Ohm C. Ampere D. Coulomb ✔ Answer: C — Ampere 5. Which particle has no charge? A. Proton B. Electron C. Neutron D. Positron ✔ Answer: C — Neutron 6. Formula for kinetic energy? A. mv B. mv² C. ½mv² D. mgh ✔ Answer: C — ½mv² 7. Which device c...