A sonometer wire of length 50cm and mass per unit length 1.0x10^-3kg m^-1 is stretched by a load of 4kg. if it is plucked at its midpoint what will be the
a) wavelength
b) frequency of the note

(take g=10Nkg^-1)

The wire's length will be the distance from node to node in the fundamental--or half the wavelength.

So the fundamental wavelength is just double the length.

The speed of the wave on the string is given by:
v = sqrt (T/mu) (see wiki website for why this is)

Frequency = speed / wavelength = sqrt (T/mu) / 2L

The load should not be given in kg. Tension is a FORCE. They probably mean the weight associated with that mass which is mg.

So frequency = sqrt (mg / mu) / 2L

They give you the loadmass and the density (mu) and the length. You know g. Plugnchug.

http://en.wikipedia.org/wiki/Vibrating_string

A sonar signal of frequency 1 106 Hz has a wavelength of 1.5 mm in water.
What is the speed of the signal in water? (m/s)

What is its period in water? (s)

What is its period in air? (s)
1 x 10^6 Hz.sorry!

V = f.wavelength = (1*10^6)*(1.5/1000) = 1 500 m/s

period in water T = 1/frequency 1/(1*10^6) = 1*10^6 s

what other information do you have ? I can't think of a way to find the period in air..

What is the relationship between wavelength, frequency, energy, and speed of propagation?

What is the relationship between wavelength, frequency, energy, and speed of propagation in terms of light spectra?
Propagation - movement in a particular direction

The higher the wavelength the higher the frequency, and the more energy the wave contains. I dont know about the speed of propagation though.

How to determine Planck's constant from a table of wavelength, frequency, and Kmax?

Hi! I'm doing my last question for my online physics homework due at 2am and I'm stuck on the very last one involving the photoelectric effect!

We are given four wavelengths along with it's corresponding Kmax value. I calculated the frequency for each wavelength too. And we have to calculate an experimental value of planck's constant based on the given values.

I know you're suppose to graph the values, but i'm not sure how. Thanks for ANY response!

What experiment is this from?\
Oh I know--photoelectric effect.

Energy of photon = hf = work function + max KE of electron

so KEmax = hf - work function

So plot KEmax vs. frequency. The slope of the line will be Planck's constant, and the intercept will be minus the work function of the metal.

If you've had a stats class, you should do a linear regression on the data to determine the slope and intercept (and error margins on each). If not, you can just eyeball the slope or take rise/run on a couple of points to get a rough estimate.

How to find the wavelength, frequency and period of the wave.?

This is a classical wave. It is traveling at 100m/s. 1.0cm of the diagram represents 1.0m in real space.

Mesure the distance between two successive crests (or troughs) and multiply it by the drawing scale: you get the wavelength.
Then: the speed=wavelength*frequency

How are wavelength, frequency, and energy related for photons of light?

A.Longer wavelength means higher frequency and lower energy.
b.There is no simple relationship because different photons travel at different speeds.
c.Longer wavelength means higher frequency and higher energy.
d.Longer wavelength means lower frequency and lower energy.
e.Longer wavelength means lower frequency and higher energy.

D) Longer wavelenght means lower frequency and lower energy.

must be the correct one.

How does the Wavelength/Frequency of Gamma rays change in the atmoshphere?

And why?

When they are inelastically scattered some of the energy is transfered from the gamma ray to the nuclei or electron that scattered it, wavelength determines energy of a photon, so the wavelength will increase because Energy = h*c / wavelength.

http://en.wikipedia.org/wiki/Compton_scattering

What is the relationship between wavelength, frequency, and energy? What is the relationship between wavelength, frequency, and energy?

The previous answer is incomplete. The relationship between frequency and energy applies only to electro - magnetic waves, and can only be understood in terms of the 'wave-particle duality' of light. All types of wave contain energy, as in the waves of the sea. However, the electro - magnetic waves that are light have a particular property that makes them different to other waves, the WAVE-PARTICLE DUALITY. Waves have certain properties that particles do not have, and particles have properties that waves do not have. Waves can be refracted when passing from one medium to another with different density, as in the well known apparent bending of light when a straight stick is immersed in water, and appears to be bent where it passes from air to water. A particle can have varying amounts of energy depending on its speed of motion, pressure and temperature. The discovery of the photoelectric effect showed that when light of a certain frequency falls on a photoelectric substance, the electrons that are caused to flow will always have energy that is proportional to the frequency of the light, and can only have this one value. This led to the conclusion that light acts like specific particles, called PHOTONS. A photon is considered to have energy but no mass, and the relationship between energy and frequency relates to the energy of the photon for that particular frequency. The constant of proportionality was worked by by a guy called PLANCK, so is known as Planck's constant, and is denoted in Physics by the letter h.
The formula E=hf gives the energy of a photon in Joules for a wave of frequency f Hertz.

The wavelength (lambda) does not appear in this equation, as wavelength = speed of light(c) divided by frequency(f), or frequency = speed of light divided by wavelength,so the equation could be written as E = h times c divided by lambda, which would yield the same result