Question

The wavelength associated with a ball of 200 a
and moving with a speed of 5 m/hour is of the
order of
(1) 10-10 m
(2) 10-20 m
(3) 10-30 m
(4) 1040 m
​

Answer 1

$\huge{\underline{\underline{Answer\::-}}}$

$\underline{\underline{Given\::-}}$

Mass of ball = 200 g or 0.2 kg

Speed of ball = 5m/hour or $\dfrac{5}{3600} m/s$

As we know that

wavelength = $\dfrac{h}{p}$

Where

h = planks constant = 6.63 × $10^{-34} J.s$

p = momentum = mass × velocity

Now

Momentum = 0.2 × $\dfrac{5}{3600} m/s$

= $\dfrac{1}{3600} kg m /sec$

Now

wavelength = $\dfrac{6.63 \times 10^{-34} J.s }{ \dfrac{1}{3600} kg m /sec }$

= $\dfrac{6.63 \times 3600 }{ 10^{34}}$ m

= $\dfrac{23868 }{ 10^{34}}$ m

= 2.39 × $10^{-30}$ m

Or of the order $10^{ - 30}$ m

Option = (3) 10 - 30 m

Hope it helps you