Ch 3 Phy Class 9
Important Easy Notes of Ch 3 Phy Class 9 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:
- Derivation and meanings of the word " dynamics ".
- Definition of dynamics
- Definition of force: symbol, mathematical form, unit, equality, nature, and examples.
- Types of forces: (1) contact forces (2) non-contact forces
- Definition of contact forces with examples.
- Definition of Non contact forces with examples.
- What is purpose and application of Newton's Law of Motion.
- State and explain Newton's first law of motion.
- Definition of inertia: explanation, factor of inertia, unit, and examples.
- Why newton is the first law of motion is also called Law of Inertia? OR what is the Law of Inertia?
- State and explain Newton's second law of motion.
- State and explain Newton's third law of motion.
- Why action-reaction cannot neutralize each other?
- Definition of mass: symbol, mathematical form, unit, nature, constant quantity, and Measuring Device.
- Definition of Weight: symbol, mathematical form, unit, nature, constant quantity, and Measuring Device.
- What is the difference between mass and weight?
- Definition of Linear Momentum: symbol, mathematical form, unit, nature, constant quantity, and Measuring Device.
- The fastest recorded speed for golf bail hits by a golfer is 75.8m/s (273 km/h). If mass of golf is 46g what is the magnitude of its magnitude?
- Relation of force and Momentum.
- Definition of isolated system with example.
- State and mathematical form derivation of Newton's Law and conservation of momentum with examples.
- Definition of collision with the explanation.
- Change of momentum and explosive forces
- Rocket propulsion and thrust.
- Definition of friction: symbol, cause, unit, nature, direction, factor, and Microscopic description of friction.
- Definition of normal force: symbol, explanation, with examples.
- Effect of normal force on friction types.
- Types of a friction: (i) static friction (ii) kinetic friction
- Definition of static friction with symbol and example
- Definition of a limiting friction with examples
- Definition of kinetic friction with examples and symbol.
- Differentiate between static and kinetic friction.
- Definition of coefficient of friction with symbol, mathematical form, and unit.
- Expression for coefficient of static friction.
- Expression for coefficient of kinetic friction
- Advantages of friction and disadvantages of friction
- Definition of rolling friction with examples
- Definition of sliding friction with examples
- Definition of atwood machine with example
- Elevator at and atwood's machine
- Definition of uniform circular motion with example
- Definition of centripetal acceleration: symbol, mathematical form, unit, Quantity, nature, Direction, figure, and examples.
- Definition of centripetal force: symbol, mathematical form, unit, quantity, nature, direction, and examples.
- Definition of centrifugal force: symbol, mathematical form, unit, quantity, nature, direction, and examples.
- Applications of centripetal force.
- Why does a dust fly off, when a hanging carpet is beaten by a stick?
- If your hands are wet and not able is handy, you can remove some of the excess water by shaking them. Why does this work?
- Why I am balloon filled with air move forward, when its air is released?
- Why does a housewife tend to move, backward when the Fireman directs a powerful stream of water towards fire?
- Your car is stuck is wet mud. Some students on their ways way to class see your product mint and help out by sitting on the truck of your car to increase its direction why does this help?
- How does a friction help you walk? Is it kinetic friction or static friction?
- The parking brake on a car causes the rear wheels to lock up. What should be the likely and consequence of applying the parking a break in a car that is in Rapid motion.
- Why is the surface of a conveyor belt made rough?
- Why does a boot man tie his boat to a pillar before allowing the passengers to step on the river bank?
- In uniform circular motion is the velocity constant is the acceleration constant? explain.
- You tie a brick to the end of a rope and while the brick around you in horizontal circle. Describe the path of the brick after you should leave letter go of the rope.
- Why is the posted speed of heart and lower than the speed limit on must highways.
- Solved Numerical of the exercise Ch 3 Phy Class 9.
- 1580kg car is travelling with a speed of 15.0 m/s. What is the magnitude of the horizontal net force that is required to bring the car to hurt in a distance of 50.0 m?
- A bullet of mass 10 g is fired with a rifle the bullet takes 0.003 s to move through a barrel and leaves with velocity of a 300 m/s. What is the force exerted on the bullet by the rifle?
- Determine the magnitude of the centripetal force exerted by the rim of a car's Wheel on a 45.0 kg tire. The tire has a 0.480m is rotating at a speed of the 30.0 m/s.
- Two bodies of masses 3kg and 5kg are tied to string which is passed over a Pulley. If the body has no friction, find the acceleration of the bodies and intention in the string.
- You want to move a 500N crate across level floor. To start the create moving you have to pull with the 230N horizontal Force. One the crate breaks laws and starts to move, you can keep it moving at constant velocity with the only 200N. What are the coefficient of the static and kinetic friction?