p5-waves basic waves, superposition, interference

Question 1

What is the Amplitude of a wave ?

Answer 1

A waves maximum displacement from the equilibrium position

Question 2

What is the wavelength of a wave?

Answer 2

The distance between two identical points on a wave/ the length of one whole oscillation

Question 3

what is the period of a wave?

Answer 3

The time it takes for the wave to repeat itself at a given point/ Time taken for one oscillation

Question 4

What is the frequency of a wave?

Answer 4

The number of complete oscillations passing through a point per second

Question 5

How are period and frequency linked ?

Answer 5

frequency=1/ period and period=1/frequency

Question 6

What is superposition?

Answer 6

When two or more waves cross at a point, the displacement at that point is equal to the sum of the displacement of individual waves.

Question 7

What is the definition of phase?

Answer 7

The position of a certain point om a wave cycle. This can be measured in radians or degrees or a fraction of a cycle

Question 8

What is phase difference?

Answer 8

How much a particle/ wave lags behind another particle/wave. This can be measured in radians, degrees or fractions of a cycle

Question 9

What is path difference?

Answer 9

The difference in distance travelled by two waves

Question 10

What is coherence?

Answer 10

when the waves have the same frequency and a constant phase difference

Question 11

What is a wavefront?

Answer 11

A wavefront is a surface which is used to represent the points of a wave which have the same phase.

Question 12

What is the phase relationship between phase difference and path difference?

Answer 12

They are directly proportional?

Question 13

What is the equation for phase difference?

Answer 13

phase difference= 360x path difference/wavelength

Question 14

What is the minima of a wave?

Answer 14

The point where a crest and a trough of two different wavefronts meet

Question 15

What is the maxima of a wave?

Answer 15

The point where two crests or two troughs of two different waves meet

Question 16

what is the equation for working out the velocity of a wave?

Answer 16

wave speed=frequency x wavelength

Question 17

What are longitudinal waves?

Answer 17

The oscillations parallel to the direction of energy transfer.
These are made up of compressions and rarefactions.
Cannot travel in a vacuum.

Question 18

What is happening at rarefactions?

Answer 18

Low pressure.
Neighbouring particles move away from one another.

Question 19

What is happening at compressions?

Answer 19

High pressure.
Neighbouring particles move towards a particle.

Question 20

What are transverse waves?

Answer 20

The oscillations are perpendicular to the direction of the wave.
Consist of peaks and troughs.
Can travel in a vacuum.

Question 21

What is an S-wave ?

Answer 21

They are transverse waves that travel through the earth in a earthquake, they can travel through liquid so arrive after P-waves as they are slower.

Question 22

What are P-waves?

Answer 22

They are longitudinal waves that travel thought the earth in a earthquake. They cannot travel through liquid and are faster so arrive at the surface first.

Question 23

What can a Displacement/ Distance graph show for a wave?

Answer 23

Shows the displacement of a particle with the distance the wave travels. Used to measure the wave length.

Question 24

What can Displacement/Time graph show for a wave?

Answer 24

Show the displacement of a particle varies with time. Can be used to measure the period of a wave.

Question 25

What is constructive interference ?

Answer 25

Occurs when the two waves are in phase, so there displacement are added.

Question 26

What is destructive interference?

Answer 26

This occurs when two waves are completely out of phase, so their displacements are subtracted.

Question 27

What is a progressive wave?

Answer 27

A wave the
at transfers energy from one point to another, without transferring matter.

Question 28

What is a standing wave?

Answer 28

A wave that transfers energy rather than transferring it from one place to another.

Question 29

What is 90 degrees in radians?( 0.25λ)

Answer 29

π/2

Question 30

What is 180 degrees in radians?(0.5λ)

Answer 30

π

Question 31

What is 270 degrees in radians?(0.75λ)

Answer 31

3π/2

Question 32

What is 360 degrees in radians?(1λ)

Answer 32

2π

Question 33

What is 540 degrees in radians?(1.5λ)

Answer 33

3π

Question 34

What in 720 degrees in radians(2λ)

Answer 34

4π

Question 35

How are standing waves formed on a string?

Answer 35

A wave reflects at a closed end meaning two identical waves are travelling in opposite directions down the same string.
The waves must be coherent for a standing wave to from.
At point where the waves meet in phase, constructive interference occurs and antinodes form.
At points where the waves meet in antiphase, destructive interference occurs and nodes are formed.

Question 36

What are nodes?

Answer 36

A node is a point of minimum displacement- there is no movement from the equilibrium position.

Question 37

What are antinodes?

Answer 37

An antinode is a point of maximum displacement.

Question 38

What factors does the speed of a transverse wave on a string depend on? (Core practical for finding the fundamental frequency)

Answer 38

Tension and mass per unit length of string( mew)

Question 39

What is the equation for working out the speed of a transverse wave on a string?

Answer 39

v=√T/μ

Question 40

What do Oscilloscopes show?

Answer 40

The time period for one wave cycle