Question 1

# Find the

(a) maximum frequency, and

(b) minimum wavelength of X-rays produced by 30 kV electrons.

(a) maximum frequency, and

(b) minimum wavelength of X-rays produced by 30 kV electrons.

Answer

Potential of the electrons, *V* = 30 kV = 3 × 104 V

Hence, energy of the electrons, *E *= 3 × 104 eV

Where,

*e* = Charge on an electron = 1.6 × 10−19 C

**(a)**Maximum frequency produced by the X-rays = *ν*

The energy of the electrons is given by the relation:

*E *= *hν*

Where,

*h* = Planck’s constant = 6.626 × 10−34 Js

So v = E / h

= 1.6 x 10^{-19} x 3 x 10^{4} / 6.626 x 10^{-34} = 7.24 x 10^{18} Hz

Hence, the maximum frequency of X-rays produced is 7.24 x 10^{18} Hz

**(b)**The minimum wavelength produced by the X-rays is given as:

λ = c / v

= 3 x 10^{8} / 7.24 x 10^{18} = 4.14 x 10^{-11} m = 0.0414 nm

Hence, the minimum wavelength of X-rays produced is 0.0414 nm.

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Sp
2018-11-10 12:05:52

instead of 104 read it 10^4

Jaseem
2017-09-10 07:40:50

Answer should be hindi ok

Jaseem
2017-09-10 07:39:51

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