Recent content by Any Help

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    The thinnest film in which the reflected light will be a max

    Homework Statement Monochromatic light, at normal incidence, strikes a thin film in air. If λ denotes the wavelength in the film, what is the thinnest film in which the reflected light will be a maximum? A λ/4 B 3λ/4 C λ D much less than λ E λ/2...
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    Two waves of light in air travel through a layer

    no only number
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    Two waves of light in air travel through a layer

    What is the name of the difference in wavelengths?
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    Two waves of light in air travel through a layer

    Homework Statement Two waves of light in air, of wavelength 550 nm, are initially in phase. They then both travel through a layer of plastic as shown in the figure, with L1 = 4.00 μm, n1 = 1.40, L2 = 3.50 μm , and n2 = 1.60. What is their phase difference after they both have emerged from the...
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    The longitudinal displacement of sound wave

    Homework Statement The longitudinal displacement of a mass element in a medium as a sound wave passes through it is given by s = sm cos (kx – ωt). Consider a sound wave of frequency 330 Hz and wavelength 0.95 m. If sm= 16 µm, what is the displacement of an element of air located at x = 1.1 m...
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    What Is the Correct Water Level for the Third Resonance in a Closed-Open Tube?

    I didn't get your point. How can I draw diagram for it? Besides why n=3 is not correct? what do they mean by the third such resonance?
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    What Is the Correct Water Level for the Third Resonance in a Closed-Open Tube?

    Homework Statement A vibrating tuning fork of frequency 512 Hz is held over a water column with one end closed and the other open. As the water level is allowed to fall, a loud sound (resonance) is heard at specific water levels. Assume you start with the tube full of water, and begin steadily...
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    Calculating Ambulance Frequency Change: -113 Hz

    1) when towards me it is FL1=Fs*v/(v-vs)=880*343/(343-22)=940 Hz when moves away from me FL2=Fs*v/(v+vs)=880*343/(343+22)=827Hz FL2-FL1=827-940=113 Hz Ah okay thanksssss
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    Doppler effect (source and detector moving together)

    Suppose we don't have a wall, then how are we supposed to find that frequency received by the person?
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    Calculating Ambulance Frequency Change: -113 Hz

    Homework Statement : An ambulance has a siren of frequency 880 Hz. You are sitting at a stop light as the ambulance passes you, traveling at a constant 22 m/s. If the speed of sound is 343 m/s, what is the change in the frequency that you hear as the ambulance passes you? A -53 Hz B...
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    Doppler effect (source and detector moving together)

    Ah then vs=vL since both are coming toward each other. then fL=976 Hz which is correct :) thanks
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    Doppler effect (source and detector moving together)

    Homework Statement A source emits sound with a frequency of 860 Hz. It is moving at 20.0 m/s toward a stationary reflecting wall. If the speed of sound is 343 m/s, what frequency does an observer riding with the source hear? A 860 Hz B 913 Hz C 910 Hz D 765 Hz...
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    Fundamental frequency of a wire wheel spoke

    Ah okay. Thanks very much. I used the diameter as a radius wrongly. :) Now it will be 877Hz which is the correct answer
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    Waves: fundamental frequency of taut cable

    T=tension=160N μ=linear mass=0.35kg/m f is the frequence
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    Fundamental frequency of a wire wheel spoke

    Homework Statement The spoke of a wire wheel is 9.5 cm long, 3.5 mm in diameter, and under tension of 2100 N. The wire is made of steel of density 7860 kg/m3. When struck with a metal tool at its center, the spoke rings at its fundamental frequency. What is that frequency? Homework Equations...