Chapter 16 & 17 - oscillations and circular motion

Question 1

radian

Answer 1

angle measurement equal to the angle at the centre of a circle subtended by an arc length equal to the radius or approximately 57.3 degrees

Question 2

centripetal force

Answer 2

net force which acts perpendicular to the direction of velocity, towards the centre of the circle

Question 3

centripetal acceleration

Answer 3

the acceleration of the object is equal to the rate of change of velocity

Question 4

period

Answer 4

time taken for an object to complete a full circle

Question 5

simple harmonic motion

Answer 5

an oscillation, where the acceleration of the oscillator is directly proportional to the displacement from the equilibrium position and acts towards the equilibrium position

Question 6

phase difference

Answer 6

the fraction of an oscillation between the position of two oscillating objects

Question 7

damping

Answer 7

the process by which the amplitude of the oscillations decrease over time, due to energy loss to resistive forces such as drag or friction

Question 8

how to investigate simple harmonic motion

Answer 8

mass on string. swing from maximum displacement. record period of one oscillation. use fiducial marker for stop/start reference

Question 9

velocity of oscillator at a given time

Answer 9

find gradient of graph at that point.

Question 10

maximum velocity of oscillation

Answer 10

equilibrium

Question 11

when is an oscillation stationary

Answer 11

at amplitude points

Question 12

maximum acceleration of oscillation

Answer 12

at amplitude points

Question 13

when is acceleration equal to zero

Answer 13

when the oscillator is in equilibrium

Question 14

energy transfers in simple harmonic motion

Answer 14

max kinetic energy at equilibrium point, where velocity is also a maximum.
maximum potential energy is at amplitude positions where displacement is at a maximum

Question 15

light damping

Answer 15

e.g. pendulums. amplitude decreases exponentially

Question 16

heavy damping

Answer 16

amplitude decreases dramatically

Question 17

critical damping

Answer 17

object stops before one oscillation is completed

Question 18

free oscillation

Answer 18

oscillating without any external forces applied, so it oscillates at a natural frequency

Question 19

forced oscillation

Answer 19

when a driving force is applied to an object, causing it to oscillate at a certain frequency

Question 20

resonance

Answer 20

occurs when driving frequency of external force applied to an object is equal to the natural frequency of the object

Question 21

amplitude

Answer 21

maximum displacement

Question 22

angular velocity

Answer 22

rate of change of angle

Question 23

investigating circular motion

Answer 23

bung (mass m) to string through tube. other end of string has weight, with mass m suspended, to provide the centripetal force.
time of one oscillation is recorded
repeat with different masses