Class 9 Ch 6 Physics
Important Easy Notes of Class 9 Ch 6 Physics English Medium written by Professor Mr. Samiullah Suib. These notes are very helpful in the preparation of Physics for students of the 9th class Physics English Medium and these are according to the paper patterns of all KPK Book Boards.
Summary and Contents:
Topics which are discussed in the notes are given below:
- Definition of work: Symbol, mathematical form, Unit, quantity, nature, factors.
- Definition of Joule: Symbol and Units.
- Definition of Energy: Symbol, mathematical form, Unit, quantity, nature, factors.
- Definition of Mechanical Energy with examples.
- Definition of Heat Energy with examples.
- Definition of Sound Energy with examples.
- Definition of Chemical Energy with examples.
- Definition of Radiant Energy with examples..
- Definition of Electrical Energy with examples.
- Definition of Nuclear Energy with examples.
- Definition of kinetic energy: Abbreviation, symbol, mathematical form, unit, quantity, nature, factors, and examples.
- Definition of Potential energy: Abbreviation, symbol, mathematical form, unit, quantity, nature, factors, and examples.
- Types of a potential energy: (i) Elastic potential energy (ii) Gravitational potential energy.
- Definition of Elastic potential energy with examples.
- Definition of gravitational potential energy with examples.
- History, statement, mathematical form, and examples of law of conservation of energy.
- History, purpose, statement, mathematical form, and examples of mass-energy Equivalence.
- Definition of Non-Renewable Sources with examples.
- Definition of fossil fuels with examples.
- Definition of geothermal energy
- Definition of wind energy and uses of wind energy.
- Advantages of Dams
- Differentiate between Renewable Sources and Non-Renewable Sources.
- Definition of Machine with its Input and Output.
- Definition of efficiency: Symbol, mathematical form, quantity, nature, unit and Note.
- Why the efficiency of an engine cannot be 100%?
- Definition of Power: Symbol, mathematical form, quantity, nature, unit and Note.
- Definition of Watt: Symbol, mathematical form, quantity, nature, unit and Note.
- Can a centripetal force ever do work on an object? explain.
- What happened to the kinetic energy of a bullet when it penetrates into a sand bag?
- A meteors enters into Earth is atmosphere and burns what happens to its kinetic energy?
- Two bullets are fired at the same time with the same kinetic energy. If one Bullet has twice the mass of the Other which has the greater speed and by what factor? Which can do the most work?
- Can an object have different amounts of gravitational potential energy if it remains at the same elevation?
- Why do roads leading to the top of a mountain wind back and forth?
- Which would have greater effect on the kinetic energy of an object doubling the mass or doubling the velocity?
- If the speed of a particle Travels by what factor does its kinetic energy increases?
- The motor of a crane uses power "P" to lift a steel beam. By what factor must the motor's power increase to left the beam twice as high in half the time?
- Solved Numerical of the exercise Class 9 Ch 6 Physics.
- Determine the work done in each of the following cases: (a) Kicking a soccer ball forward with a force of 40N over a distance of 15cm. (b) Lifting a 50 kg barbell straight up 1.95m.
- Calculate the gravitational potential energy of a piano of mass 200kg (a) piano resting on the floor. (b) With respect to a basement floor 1.9m below.
- What power is required for a ski-hill chair lift that transport 500 people (average mass 65kg) per hour to an increased elevation of 1200m?
- How long will it take a 2750W motor to lift a 385kg sofa set to a sixth story window 16.0m above?
- How much work can a 2.0hp motor do in 1.0h?