Question

A ball of 100 g mass is thrown with a velocity of $100m{s}^{-1}$. The wavelength of the de Broglie wave associated with the ball is about:

• A. $6.63\times {10}^{-35}m$
• B. $6.63\times {10}^{-30}m$
• C. $6.63\times {10}^{-35}cm$
• D. $6.63\times {10}^{-33}m$

Answer 1

The correct option is A $6.63\times {10}^{-35}m$

$\lambda =\frac{h}{mv}$

$\lambda ⟶$De Broglie wavelength

m=100 g=$\frac{100}{1000}$ kg=0.1 kg

v=100 ms${}^{-1}$

$\lambda =\frac{h}{mv}=\frac{6.623\times {10}^{-34}}{0.1\times 100}=6.626\times {10}^{-35}m$