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JEE Main 202125 FebruaryEvening Shift

Exam: JEE Main
Year: 2021
Date: 25 February
Shift: Evening Shift
Subject: Physics
Chapter: Electromagnetic Waves

JEE Main 2021 · 25 February · Evening Shift · Physics · Electromagnetic Waves

The wavelength of an X-ray beam is 10 Å . The mass of a fictitious...

The wavelength of an X-ray beam is

10 Å

. The mass of a fictitious particle having the same energy as that of the X-ray photons is

\dfrac{x}{3}hkg .

The value of

x

is ___ . (

h =

Planck's constant)

Correct answer

0

Step-by-step solution

$\dfrac{hc}{\lambda} = m{c}^{2}$

$⇒ m = \dfrac{h}{c\lambda} = \dfrac{h}{3 \times {10}^{8} \times 10 \times {10}^{- 10}} = \dfrac{10h}{3}kg$

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