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CBSE **Class 12th Physics** Notes: **Dual Nature** of **Radiation** and ...

Jan 19, 2017 **...** CBSE **class 12** chapter wise notes based on chapter 11, **Dual Nature** of
**Radiation** and **Matter**, of **class 12 NCERT Physics** textbook are available in this
article. ... **Photoelectric Effect** and **Wave Theory** of **Light**. **Photon**. **Einstein's**
**Photoelectric Equation**: **Energy Quantum** of **Radiation**. Threshold frequency.

For more information, see CBSE **Class 12th Physics** Notes: **Dual Nature** of **Radiation** and ...

Given that

Total energy of two rays 2E = 10.2 BeV

2E = 10.2 * 10^9 eV

2E = 10.2 * 10^9 * 1.6*10^{-10} J

Energy of ray E = \frac{10.2 * 10^9 * 1.6*10^{-10}}{2} J

E = 8.16 *10^{-10} J

Step 1: Finding the wavelength of y-rays

Energy of proton E=h\upsilon\ =\ \frac{hc}{\lambda}

Where, h - Planck's constant( 6.63*10^{-34} Js}), speed of light c = 3*10^{8} m/s and \upsilon - frequency.

\lambda = \frac{h c}{ E }

\lambda = \frac{(6.63*10^{-34})*(3* 10^{8})}{8.16 *10^{-10}}

\lambda = 2.436 * 10^{-16} m

Therefore, wavelength of y-rays \lambda = 2.436 * 10^{-16} m