That's a great question Harold! I'm not sure i can answer here but i'll give it a try. Speed of waves typically depend on 2 things - restoring forces divided by inertial terms - for waves on a string we get v=sqrt(T/mass density). So if i thin string is connected to a larger one and keep the tension uniform the wave on a thin string will have a faster speed because it's mass density is smaller. The frequency will depend on the source - in this case the person holding the thin string moving their hand up and down. At some point the thin string is connected to the larger one. At this point the frequency must be the same on both sides - otherwise the string is going in different directions. At the end if the speed changes - (medium changes)- frequency is the same - wavelength has to also change. For electromagnetic waves the arguments are a little more complicated but similar. The speed of the light in medium depends on the properties of the medium. The frequency depends on the source only (whats doing the shaking up and downs to create the electromagnetic waves) At the boundary the frequency must be the same otherwise there would be mismatch between the waves in different medium which would violate several laws of physics (Maxwell's Equation).
Make sure your calculator is in degrees and not radians. On a TI-83 or similar calculators, you should be able to do (2nd)(sin^-1) and that will open parenthesis. Type in (1/1.33) and hit enter. Should get the 48.75 degrees.
your way of explaining physics is crazy good.
This is a great explanation 👍🏻
great explanation, thank you!
when you wrote the case descriptions on the left you wrote N2>N1 twice.
Great video. Hoping you can clear something up for me. How does wavelength change, but frequency does not? I have been beating myself up on this one.
That's a great question Harold! I'm not sure i can answer here but i'll give it a try. Speed of waves typically depend on 2 things - restoring forces divided by inertial terms - for waves on a string we get v=sqrt(T/mass density). So if i thin string is connected to a larger one and keep the tension uniform the wave on a thin string will have a faster speed because it's mass density is smaller. The frequency will depend on the source - in this case the person holding the thin string moving their hand up and down. At some point the thin string is connected to the larger one. At this point the frequency must be the same on both sides - otherwise the string is going in different directions. At the end if the speed changes - (medium changes)- frequency is the same - wavelength has to also change. For electromagnetic waves the arguments are a little more complicated but similar. The speed of the light in medium depends on the properties of the medium. The frequency depends on the source only (whats doing the shaking up and downs to create the electromagnetic waves) At the boundary the frequency must be the same otherwise there would be mismatch between the waves in different medium which would violate several laws of physics (Maxwell's Equation).
can light be reflected even if total refraction occurs?
Yes
thank you
I’m unable to get this answer in my calculator 😔
Make sure your calculator is in degrees and not radians. On a TI-83 or similar calculators, you should be able to do (2nd)(sin^-1) and that will open parenthesis. Type in (1/1.33) and hit enter. Should get the 48.75 degrees.