Class 11 Physics Ch 5 Notes

• Important from class 11 physics ch 5 important questions Punjab Textbook.
• Define angular displacement. And write its unit.: Ans: “The angle subtended at the center of a circle by a body moving along the circumference in a given time is called angular displacement. It is denoted by Δθ” Unit: Its S.I unit is radian. 
• State right hand rule to find the direction of angular displacement.
• What is the difference between a degree and radian?
• Define angular velocity (angular frequency). Give its formula and unit. How can we find the direction of angular velocity?
• Define angular acceleration and instantaneous acceleration. Write its formula and unit.
• Define positive angular acceleration and negative angular acceleration.
• Drive the relation between linear velocity and angular velocity. OR Prove that v = rω
• Drive the relation between linear acceleration and angular acceleration. OR Prove that a = rα  
• Define centripetal acceleration and centripetal force.
• Important from class 11 physics ch 5 question answer Punjab Textbook.
• Define moment of inertia. How it is related to torque.
• Give practical uses of rotational K.E by fly wheels.
• What is difference between real and apparent weight?
• What is artificial gravity? Write down expression for its frequency.
• Define geostationary satellites. And write down its uses.
• Important from class 11 physics ch 5 numericals Punjab Textbook.
• What is meant by INTELSAT? AT what frequencies the, INTELSAT – IV operates?
• What is the main difference between Newton’s and Einstein view of gravitation?
• Explain the difference between tangential velocity and the angular velocity, if one of these given for a wheel of known radius, how will you find the other?
• Important from class 11 physics ch 5 exercise solutions Punjab Textbook.
• Explain what is meant by centripetal force and why it must be furnished to an object if the object is to follow a circular path?
• What is meant by moment of inertia? Explain its significance: Ans: The moment of inertia of a particle is defined as the product of mass and the square of its perpendicular distance from axis of rotation. Mathematically, 2 I = mr Physical meaning: The moment of inertia plays same role during angular motion which plays mass during linear motion. Mass is the measure of linear inertia while moment of inertia measures of rotational inertia of a body. Moment of inertia determine the angular acceleration while mass determine the linear acceleration.
• What is meant by angular momentum? Explain the law of conservation of angular momentum?
• Describe what should be the minimum velocity, for a satellite, to orbit close to the earth around it.
• State the direction of the following vectors in simple situation; angular momentum and angular velocity. 
• Explain why an object, orbiting the earth, is said to be freely falling. Use your explanation to point out why objects appear weightless under certain circumstances.
• Important from class 11 physics ch 5 imp questions Punjab Textbook.
• When mud flies off the tyre of a moving bicycle, in what direction does it fly? Explain it. 
• A disc and a hoop start moving down from the top of an inclined plane at the same time. Which one will be moving faster on reaching the bottom?
• Why does a diver change its positions before and after diving in the pool?
• A student holds two dump-bells stretched arms while sitting on a turn table. He is given a push until he is rotating at certain angular velocity. The student then pulls the dumb-bells towards his chest. What will be the effect on rate of rotation? 
• Explain how many minimum number of geo-stationary satellites are required for global coverage of T.V transmission.