### Browsed byCategory: waves

Leslie speaker, Doppler effect and the Nobel Prize in Physics 2019

## Leslie speaker, Doppler effect and the Nobel Prize in Physics 2019

The Nobel Prize in Physics 2019 was awarded “for contributions to our understanding of the evolution of the universe and Earth’s place in the cosmos” with one half to James Peebles “for theoretical discoveries in physical cosmology”, the other half jointly to Michel Mayor and Didier Queloz “for the discovery of an exoplanet orbiting a solar-type star.” In this sub-section we will try to understand how Michel Mayor and Didier Queloz discovered the first ever exoplanet – 51 Pegasi b…

Rolling Shutter and online guitar videos

## Rolling Shutter and online guitar videos

When you search for videos online of plucking a string on an instrument such as the guitar, a surprising number of searches lead you to videos such as the following: This is not how plucked strings look like! And they don’t have anything to do with Harmonics either! The reason why you are seeing those shapes on the guitar is due to the rolling shutter effect on your camera. But if you do want to see how plucked strings look…

Visualizing Doppler Effect using ripple tanks

## Visualizing Doppler Effect using ripple tanks

Ripple tanks are really cool ways to explore the way a wave behaves under the influence of a perturbation. They are fairly simple to make, and are usually available in college and school laboratories to render better understanding of the wave phenomenon. How does it work ?                    Source There is a usually an oscillating paddle( above– used to produce plane waves) or a point source/s ( below – used to produce circular waves ) which are actuated by eccentric…

Even and Odd Harmonics of a vibrating string

## Even and Odd Harmonics of a vibrating string

In the previous section we took a look at the vibrating string fixed at both ends and found that in order for the boundary condition to be satisfied, the following are the only solutions possible: The solutions on the left of the image are often termed as ‘Odd Harmonics’ because they have odd number of anti-nodes and the ones of the right have even number of anti-nodes hence ‘Even Harmonics’ If you pluck a string right at the center, you…

Standing Waves

## Standing Waves

If you have a solid understanding of what Traveling waves are (click here if you need a refresher) then when you add up a sine wave moving to the right with a wave moving to the left, you get a standing wave. $y(x,t) = \sin(kx-\omega t) + \sin(kx + \omega t)$ Using $\sin(a) + \sin(b) = 2 \sin((a+b)/2) \cos((a-b)/2)$ and simplifying the above equation we get : $y(x,t) = 2\sin(kx)\cos(\omega t)$ A plot of this…