Waves Flashcards
What is amplitude
The maximum displacement of a point on a wave from its in disturbed position
What is a wave
A wave transfers energy from one place to another without transferring matter
What is oscillation
The vibration of a particle around a fixed position
What is a longitudinal wave
Oscillation are parallel to the direction of energy transfers causing compression
What are examples of longitudinal waves
Sound
Seismic
P waves
How do longitudinal waves travel
Through a series of compression and refractions
What are transverse wave s
The oscillation of the waves are perpendicular to the direction in which the wave is trandferrring energy causing compressions
What are examples of transverse waves
Electromagnetic waves
Light
Gamma
Microwaves
What are mechanical waves
They travel through a substance
How are electromagnetic waves different
They travel through a vacuum no substance is needed
What is wave length
The lengths of a wave from one compression to another
What is time period
The time taken for one wave to pass a point per second
What is frequancy
The number of waves that pass a point per seconds
What is the formula for wave speed
Wave speed (v)= frequancy x wave length
What do waves do when they meet a change in medium
Reflect
Be Absorbed
Travel through(transmit)
What is refraction
It is the change of direction of the wave due to the change of speed when entering a new medium (bend)
Why does refraction occur
When the speed of the wave changes
Due to the density of materials
What is reflection
When a wave rebounds of a medium
Why do waves slow down in different substances
Due to the increase of optical density
Why do waves bend if it hits denser material at an angle
The wave front hit the medium at a different time thus causing a bend
When doe waves not refract in a medium
When it is hitting the medium a t 90 degrees as the wave front hits the medium at the same time
How do we change the speed of waves in water
By changing the depth or shallowness of the water as you can’t change the density
What is an example of sound reflecting
Echos
What are wave fronts
Lines that are used to represent the peaks of transverse waves and compressions of longitudinal waves
What is the law of reflection
The angle of the incidence= the angle of reflect
What type of waves are the ripples on a water surface
Transverse
What is the advantage of repeating measurements and calculating a mean
To reduce the effects of random errors
How do we find frequency from a time period
1 / time period
Plain how the teacher could determine the speed of the wave using a ripple tank without measuring the wavelength of the wave
Measure distance travelled by a wave using a meter ruler
Measure the time taken for a wave to travel to measure distance with a timer
Divide distance by time
Explain why the ray of light from a Reebok should be as narrow as possible when experimenting refraction
It is harder to judge where the centre of a wide array is hence causing a larger uncertainty
How do we find uncertainty
Range divided by two
A student is using a car Remote control to drive a toy car car aerial of the toilet is connected to an electrical circuit in the car describe what happens in the electrical circuit when the car aerial absorbs radio waves from the car remote control
Alternating current is induced in the electrical circuit with the same frequency as the radio wave
Explain why a car has maximum speed
There is a maximum forward force therefore as the speed increases air resistance increases until the air resistance is equal to the forward force therefore the car cannot accelerate anymore
Explain an experiment of measuring the speed of water using a ripple tank
Use a signal generator attached to the good part of a ripple tank to create water waves at a set to frequency.
Place A white sheet of paper under the ripple tank and a meter ruler on the edge of the paper. Then place a lamp on top of the water
Dim the lights in the lamp and turn on the lamp you should see the wave as shadows on the screen below the tank .
Distance between Each shadow lines are equal to one wavelength
Measure the distance between the shadow lines there are 10 wave lengths apart the divide the distance by 10 to get frequancy
Then use the equation for wave speed
Why is it suitable to use a ripple tank to measure the speed of Waves
Because it allows you to measure the wavelength without disturbing the waves
How do you find the wavelength of a string on the string exper
Meausere multiple half wave using a ruler then find the mean of them and double to find full wave length
How can u make it easier to measure waves on a ripple tank
Use a strobe light.
When the strobe lights frequancy matches the waves frequancy the waves will appear stationary so u can measure it
How do u sat up the string experiment to measure speed
Connect a string over a pulley to a vibration transducer. Then connect the signal generator to the vibration transducer and switch on. Adjust the frequancy of the signal generator to produce clear waves.
