Physics Unit 3 (9)

Physics Unit 3 (9)

1. A simple pendulum

   • Gravity provides a centriprtal force that keep s planets and satellites in orbit. Gravity is stronger between objects that re closer together so these objects travel faster in their orbit.
   • A pendulum is a mass on a string that can swing freely. e.g swing or fairground rides.
   • At the highest point of its swing , the pendulum briefly stops and stores energy as gravitational potential energy.
   • At the lowest swing , this energy is transferred to kinetic energy as the pendulum travels fastest.
   • The time period of a pendulum , T is calculated using T=1/F
     • where T is the periodic time in seconds and the f is the frequency in hertz.
   • The longer the pendulum, the longer its time period.

2. Long pendulums

   • Changing the mass of a pendulum does not change the time period of a pendulum.