XI Physics Important Qns

INTERNATIONAL INDIAN SCHOOL, RIYADH, K.S.A XI_PHYSICS_Important Questions -Mohammad Abdul Mumeed, Physics Teacher-I.I.S.R +966507433412 1 © Md. Abdul Mumeed, Senior Secondary Teacher in PHYSICS at I. I. School, Riyadh, K.S.A. Note: You may be given short answer questions (for conceptual and HOTS), numerical problems or direct derivations from few of the following IMPORTANT QUESTIONS. 1. Explain in detail about the systematic and random errors. 2. How do you calculate the error in the i. Sum or difference ii. Product or quotient iii. Powers of different measured quantities 3. Explain the rules for rounding off numbers and rules for arithmetic operations with significant figures. 4. What is Parallelogram law of addition of vectors? Derive an expression for the magnitude and direction of the resultant vector using parallelogram law. 5. Define Scalar product and Vector product of the two vector quantities. And also give two examples for each. 6. Show that time of ascent of a vertically projected object is equal to its time of descent. 7. Show that the trajectory of an object thrown horizontally from tower of certain height (OR)an object thrown at certain angle with the horizontal is a parabolic. 8. Derive an equation for the maximum height and range of an object projected at certain angle with the horizontal. 9. Show that Newton’s first law of motion is contained in the second law of motion. 10. If action and reaction are always equal and opposite, explain how a cart drawn by a horse moves forward. 11. Define impulse. Give its S.I. unit 12. Define co-efficient of static and dynamic frictions. Derive expression for the acceleration of the body sliding on a horizontal plane having coefficient of friction µk. 13. Derive an expression for acceleration of a body moving down a rough inclined plane. 14. State the law of conservation of energy and prove it in the case of a freely falling object (or) a body projected vertically upwards. 15. Discuss how apparent weight of a person in a lift changes when it is a) Moving up with acceleration b) Moving down with acceleration INTERNATIONAL INDIAN SCHOOL, RIYADH, K.S.A XI_PHYSICS_Important Questions -Mohammad Abdul Mumeed, Physics Teacher-I.I.S.R +966507433412 2 © Md. Abdul Mumeed, Senior Secondary Teacher in PHYSICS at I. I. School, Riyadh, K.S.A. c) Moving with uniform velocity d) When it is stationary 16. Deduce an expression for P.E. stored in a spring. 17. Show that in the case of one dimensional elastic collision, the relative velocity of approach of two colliding bodies before collision is equal to the relative velocity of separation after collision. 18. Distinguish between elastic and inelastic collisions giving one similarity and one difference. And also give an example of each. 19. State law of conservation of angular momentum and explain with two examples. 20. Derive relation between torque and angular momentum. 21. State Parallel and Perpendicular axes theorems. 22. Derive an expression for the variation of acceleration due to gravity with altitude and depth at a place on the earth. 23. Deduce an expression for gravitational P.E. And also derive expression for gravitational Potential. 24. Derive an expression for orbital velocity. And also derive an expression for escape velocity. 25. Describe Hook’s law of elasticity. Define three different types of moduli. 26. Describe the behavior of a wire under increasing load. Explain the terms proportionality limit, elastic limit, permanent set and breading stress. 27. Obtain an expression for the pressure inside a liquid drop (or a liquid bubble) 28. Deduce an expression for the rise of liquid in a capillary tube. 29. State and prove Bernoulli’s theorem. 30. What do you understand by the term “terminal velocity”? Obtain an expression for the terminal velocity of an object moving thorough a fluid. 31. What is dynamic lift and explain the role of dynamic lift during the take off of an aeroplane. 32. Derive expression for equation of continuity. 33. Define three coefficients of expansions of solids and deduce the relation between them. INTERNATIONAL INDIAN SCHOOL, RIYADH, K.S.A XI_PHYSICS_Important Questions -Mohammad Abdul Mumeed, Physics Teacher-I.I.S.R +966507433412 3 © Md. Abdul Mumeed, Senior Secondary Teacher in PHYSICS at I. I. School, Riyadh, K.S.A. 34. Explain the working of a heat engine and a refrigerator with a labeled block diagram giving efficiency and coefficient of performance. 35. Explain why gases have two specific heats. Show that Cp – Cv = R in case of 1 mole of an ideal gas. 36. Show that the motion of a simple pendulum is simple harmonic and derive an equation for its time-period. 37. Show that the total energy of an object in SHM is constant at any point on its path. 38. Derive an equation for the time period of a loaded spring. 39. Using displacement equation for an object undergoing SHM, derive velocity and acceleration expressions. And also plot a sketch graph to show the variation of each of the following on same scale of x-axis. i) Displacement –time graph ii) Velocity-time graph iii) Acceleration-time graph 40. Derive expression for frequency ratio of higher harmonics in case of a closed pipe. 41. Derive expression for frequency ratio of higher harmonics in case of an open pipe. 42. Derive expression for frequency ratio of higher harmonics in case of a stretched string. 43. Deduce expression for Doppler Effect for all the possible cases producing relative motion between source and observer. 44. Explain formation of beats. 45. Derive equation for K.E. & P.E. of a simple harmonic oscillator, and hence give expression for its T.E. And also plot a single sketch graph to show variation of KE, PE and TE with position for the simple harmonic oscillator.