Calculating De Broglie Wavelength of a 100g Ball

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The de Broglie wavelength of a 100-gram ball traveling at 100 miles per hour is calculated to be 1.48 x 10^(-24) angstroms using the formula λ = h/p. While the approach to calculating this wavelength is correct, measuring such a small wavelength poses significant challenges. The proposed method of using Compton scattering is impractical, as the wavelength is much smaller than any realistic target size. Additionally, precise measurements of trajectory angle are crucial for accurate calculations, and slight errors could lead to significant discrepancies. Alternative methods like diffraction also face limitations, making practical measurement difficult.
Rachael_Victoria
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Ok so my homework question says find the de broglie wavelength of a 100 gram ball traveling at 100 miles per hour. So do a little dimensional analysis and 100 mph is 44.704 m/s and since the de broglie wavelength is found with lamda=h/p and p=mv then I am good to go, I get 1.48 x 10^(-24) angstroms for my wavelength.
It then goes on to say "is there any experimental method by which a wavelength of this size might be measured?" So I was thinking you could throw that ball at something stationary, use the equation for compton scattered wavelength and replace c with v (or the 44.704 m/s) and theta with the angle of trajectory, this would give you a calculated wavelength for the ball after having hit something. Then measure the new velocity after impact and actually calculate the new wavelength using the de broglie equation. Am i way off?
thanks
rachael
 
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Compton scattering is when a photon scatters against an electron. The photon is a relativistic particle; you can't use the same idea with a 100 gram ball.

Find the approximate sizes of atoms, nuclei and so. Then compare it with your 10^{-24} angstrom.
 


Your approach to calculating the de Broglie wavelength of the 100 gram ball is correct. Using the equation λ = h/mv, we can calculate the wavelength to be 1.48 x 10^(-24) angstroms.

As for the experimental method to measure such a small wavelength, your idea of using Compton scattering could work. However, there are some limitations to consider. Firstly, the wavelength of the ball would have to be comparable to the size of the target it is being thrown at. In this case, the wavelength is much smaller than the size of any target we could realistically use. Additionally, the angle of trajectory would have to be precisely measured in order to accurately calculate the new wavelength using the de Broglie equation. Any slight error in the angle measurement could result in a significantly different calculated wavelength.

Another possible method could be to use diffraction. If the ball is thrown through a narrow slit or passed through a diffraction grating, the resulting diffraction pattern could be used to calculate the wavelength. However, the ball would have to be thrown with a very precise velocity and angle in order to produce a measurable diffraction pattern.

Overall, while your idea of using Compton scattering is on the right track, it may not be a practical method for measuring the de Broglie wavelength of a 100 gram ball. Other methods, such as diffraction, may also have limitations.
 
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