What is the de Broglie Wavelength of a Running Fullback?

AI Thread Summary
The discussion focuses on calculating the de Broglie wavelength of a 220lb fullback running the 40-yard dash at a speed of 19.6 mi/h. The formula used for the calculation is λ=h/(mu), where h is Planck's constant, m is mass in kg, and u is speed in m/s. The initial attempt at conversion for speed resulted in an incorrect value of 113550 m/s, while the mass conversion from pounds to kilograms was correctly calculated as 99.792 kg. The calculated wavelength was found to be 5.847 x 10^-41 m, which differs from the book's answer of 7.6 x 10^-37 m, indicating a potential error in the speed conversion. The discussion emphasizes the importance of accurate unit conversions in physics calculations.
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Homework Statement


A 220lb fullback runs the 40-yd dash at a speed of 19.6 ± 0.1 mi/h. What is he de Broglie wavelength (in meters)?


Homework Equations


de Broglie Wavelength: λ=h/(mu), where λ=wavelenght, h=6.626 x 10^(-34) kgm^2)/s, m=mass (kg), and u= speed


The Attempt at a Solution


u=19.6 m/s x (1m / 0.6214mi) x (3600s / 1h) = 113550 m/s

m= 220lb x (0.4536kg/ 1lb) = 99.792kg

λ= [6.626 x 10^(-34) kgm^2)/s] / [99.792kg x 113550 m/s]
=5.847 x 10^-41 m (MY ANSWER)

The answer in the back of the book is 7.6 x 10^-37 m
 
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1m / 0.6214mi

This conversion is incorrect 1 km = 0.6241 miles.
 
u=19.6 m/s x ...

Recheck the units here.
 
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