Vibrations 3.2

Question 1

Period?

Answer 1

Time taken for 1 complete oscillation.

Question 2

Frequency?

Answer 2

number of oscillations per second

Question 3

3 assumptions within simple harmonic motion.

Answer 3

1. theta is small
2. only concerned with motion in horizontal direction.
3. sin(theta = theta

Question 4

Simple harmonic motion?

Answer 4

Magnitude of acceleration is directly proportional to displacement of the particle and acts in the opposite direction.

Question 5

equation for S.H.M?

Answer 5

acceleration = -spring constant X displacement

or sometimes acceleration = -angular velocity X displacement

Question 6

Damping?

Answer 6

oscillating system will experience resistive forces (air) this opposes motion so it gradually reduces the amplitude of the oscillation.

Question 7

Weak Damping?

Answer 7

still has oscillations - gets less pronounced.

Question 8

Strong damping?

Answer 8

removes oscillations before a single oscillation is completed.

Question 9

Critical damping?

Answer 9

occurs between weak and strong damping when the motion jumps between the 2.

Question 10

Resonance?

Answer 10

when supplied energy is in phase with the object resonance occurs. this increases the amplitude as energy is added.

Question 11

example of resonance?

Answer 11

swing

Question 12

good uses for resonance?

Answer 12

swing, radio, microwaves

Question 13

Bad uses for resonance?

Answer 13

Bridge, car suspension, cup+singer

Question 14

define amplitude?

Answer 14

max displacement from equilibrium position.

Question 15

forced oscillation?

Answer 15

driving force is applied to an oscillatory system causing it to oscillate with the frequency of the driving force.