Class 9th Unit 3 Dynamics Centripetal force
- 1. CENTRIPETAL FORCE UNIT 3: DYNAMICS
- 2. What is centripetal force
- 3. EXAMPLES Spinning a ball tied with a string: Here the centripetal force is provided by the force of tension on the rope pulls the object in toward the centre. Turning a car: Here the centripetal force is provided by the frictional force between the ground and the wheels. Planets orbiting around the Sun: Centripetal Force is provided by Gravity.
- 5. What is the formula of centripetal force According to Newton second law of motion a net force causes acceleration in the body. Hence centripetal force Fc causes centripetal acceleration in the body moving in circle. Mathematically Fc = mac But, centripetal acceleration = ac = 𝑣2 𝑟 -- Fc = 𝑚𝑣2 𝑟 This formula shows that centripetal force needed by a body moving in circle depends on mass of body, square of velocity, radius r of circle.
- 6. CENTRIFUGAL FORCE Centrifugal force is the reaction of centripetal force. It is equal in magnitude and opposite in direction of centripetal force.
- 7. APPLICATIONS OF CENTRIFUGAL FORCE • BANKING OF THE ROADS • WASHING MACHINE DRYER • CREAM SEPERATOR
- 8. BANKING OF THE ROADS • Banking of roads is the phenomenon in which the edges are raised for the curved roads above the inner edge. • The friction between the tyres and the road provides necessary centripetal force. • If friction is not enough, the car would skid. • Banking causes a component of weight of vehicle to provide the necessary centripetal force while taking a turn.
- 10. WASHING MACHINE DRYER • The dryer of washing machine is basket spinner, having a perforated wall with many fine holes. • The centripetal force between clothes and inside of drum pushes them around in circle. • As a reaction, centrifugal force makes water fly out and get clothes dry. • Clothes experience centripetal force but water does not. Clothes go round in a circle, the water goes in straight line… straight through the holes.
- 12. CREAM SEPARATOR • Cream separators are used to remove the fat content of various products. • A separator is high speed spinner and acts on the principal of centrifuge machines . The bowl spins at high speed, pushes lighter contents (cream/ butterfat) inward and heavier contents outward. • Skimmed milk (denser than cream) is collected at outer wall • The cream is pushed towards center and collected through pipe.