waves

Question 1

what are waves? (2 marks)

Answer 1

-waves transfer energy without transferring matter
-particles oscillate around a fixed point

Question 2

two types of waves?

Answer 2

Longitudinal
Transverse

Question 3

Longitudinal: describe the vibrations

Answer 3

the vibrations are parallel to direction of travel

Question 4

Longitudinal: Two parts of longitudinal waves and where are they?

Answer 4

Compression- closer waves
Rarefraction- Further away waves

Question 5

Transverse waves: describe the vibrations

Answer 5

The vibrations of transverse waves are at 90-degree angle to the direction of travel

Question 6

Transverse: Two parts of transverse waves?

Answer 6

Peaks and troughs
peaks- the highest point above rest position
troughs-lowest point below rest position

Question 7

Differences between longitudinal and transverse waves: (2 points each)

Answer 7

Longitudinal:
-vibrations are parallel to direction of travel
-they have compressions and refractions

Transverse:
-vibrations are at a 90-degree angle
-they have peaks and troughs

Question 8

Keywords:
Amplitude

Answer 8

-Distance from the equilibrium to the peak or trough of a wave

Question 9

Wavefront

Answer 9

• a wavefront is used to represent a single wave

Question 10

Frequency

Answer 10

-the number of waves passing a point in a second (Hz)

Question 11

Wavelength

Answer 11

-Distance between two peaks on one wave

Question 12

Time period

Answer 12

-Time taken for a wave to pass a point

Question 13

wavespeed equation

Answer 13

waves speed (m/s) =frequency (hz) x wavelength (m)

Question 14

frequency equation

Answer 14

frequency=1/time period (s)

Question 15

types of longitudinal waves:

Answer 15

Sound waves
P waves

Question 16

types of transverse waves:

Answer 16

Electromagnetic waves (which can move in a vacuum)
Ripples on the surface of water
s waves

Question 17

what is the doppler effect:

Answer 17

-the apparent change
-in wavelength and frequency of a wave
-emitted by a moving source

Question 18

Describe the doppler effect in terms of frequency:

Answer 18

the pitch goes from high to low frequency as a vehicle passes by

Question 19

what happens to waves when an object is moving?

Answer 19

waves get squashed together at one end of the object and stretched on the other end

Question 20

when an object is moving (in terms of wave speed, frequency and wavelength..

Answer 20

wave speed is constant
frequency increases
wavelength decreases

Question 21

waves can be…
(hint: two r’s)

Answer 21

reflected and refracted

Question 22

what is the hearing range for humans?

Answer 22

20-20 000 Hz (hertz)

Question 23

speed of sound in air practical
equipment:

Answer 23

-Two humans
-One balloon
-One stopwatch
-Trundle wheel

Question 24

speed of sound in air practical
method:

Answer 24

-Measure the distance between person 1 and 2 using a trundle wheel
-Person 1 pops the balloon
-Person 2 starts the stopwatch when balloon is popped
-repeat 3x and calculate an average

Question 25

speed of sound in air practical
(what do you do to improve accuracy) 2 points

Answer 25

-two people swap ends to counter any wind effects
-Move further away from each other to make the reaction of time more accurate

Question 26

pitch in terms of frequency..

Answer 26

the higher the frequency, the higher the pitch

Question 27

sound in terms of amplitude…

Answer 27

the higher the amplitude, the louder the sound