Question

What will be the wavelength of a ball of mass 0.1 kg moving with a velocity of $10m{s}^{-1}$?

• A. 6.6× 10^-34 m
• B. 7.8× 10^-40 m
• C. 8.7× 10^-30 m
• D. None of these

Answer 1

The correct option is

A

6.6× 10^-34 m

λ=h/p (or) λ=h/mv

Where,

p = linear momentum (mv) ,

h = Planck constant = 6.626×${10}^{-34}$ Js ,

m = mass

v = velocity.

In the given details,

Mass of ball ( m ) = 0.1kg ,

Velocity of ball ( v ) = 10ms−1 ,

$\lambda =\frac{h}{mv}$ = $\frac{6.626\times {10}^{-34}}{\left(0.1kg\right)\left(10m{s}^{-1}\right)}$

$=6.626\times$ ${10}^{-34}m(\because J=kg{m}^2$ $s^{-2})$