The wavelength of an X-ray beam is 10$\mathop A\limits^o$. The mass of a fictitious particle having the same energy as that of the X-ray photons is ${x \over 3}h$ kg. The value of x is __________. (h = Planck's constant)
Answer (integer)
10
Solution
Given wavelength of an x-ray beam = 10$\mathop A\limits^o$<br><br>$\because$ E = ${{hc} \over \lambda } = m{c^2}$<br><br>$\Rightarrow$ m = ${h \over {c\lambda }}$<br><br>The mass of a fictitious particle having the same energy as that of the x-ray photons = ${x \over 3}$h kg<br><br>$\therefore$ ${x \over 3}h = {h \over {c\lambda }}$<br><br>$x = {3 \over {c\lambda }}$<br><br>$= {3 \over {3 \times {{10}^8} \times 10 \times {{10}^{ - 10}}}}$<br><br>x = 10
About this question
Subject: Physics · Chapter: Electromagnetic Waves · Topic: Properties of EM Waves
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