The wavelength of K_a X-rays produced by an X-ray tube is 0.76 $\stackrel{\circ }{A}$. Find the atomic number of the anode material of the tube?

1. 41

2. 30

3. 20

4. 10

 An x-ray tube is operating at 30 kV then the minimum wavelength of the x-rays coming out of the tube is:

1. 1.24 $\stackrel{0}{A}$

2. 0.413 $\stackrel{0}{A}$ 

3. 0.124 $\stackrel{0}{A}$ 

4. 0.13 $\stackrel{0}{A}$

Bragg's law for X-rays is:

1. dsin$\theta$ = 2n$\lambda$ 

2. 2dsin$\theta$ = n$\lambda$

3. nsin$\theta$ = 2$\lambda$d

4. None of these

The minimum wavelength of X-rays produced by electrons accelerated by a potential difference of V volt is equal to 

1. $\frac{eV}{hc}$ 

2. $\frac{eh}{cV}$ 

3. $\frac{hc}{eV}$ 

4. $\frac{cV}{eh}$

The graph between the square root of the frequency of a specific line of the characteristic spectrum of X-rays and the atomic number of the target will be:

1.
2.
3.
4.

The wavelength of $K_{\alpha }$ X-rays for lead isotopes $P{b}^{208},<mspace\; width="1em"></mspace>P{b}^{206},<mspace\; width="1em"></mspace>P{b}^{204}<mspace\; width="1em"></mspace>are<mspace\; width="1em"></mspace>{\lambda }_1,<mspace\; width="1em"></mspace>{\lambda }_2<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>{\lambda }_3$ respectively. Then

1. ${\lambda }_1={\lambda }_2>{\lambda }_3$   

2. ${\lambda }_1>{\lambda }_2>{\lambda }_3$

3. ${\lambda }_1<{\lambda }_2<{\lambda }_3$ 

4. ${\lambda }_2={\lambda }_1={\lambda }_3$

which of the following is positively charged?

1.  $\mathrm{\alpha }-\mathrm{particles}<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>$

2.  $\mathrm{\beta }-\mathrm{particles}<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>$

3.  $\mathrm{\gamma }-\mathrm{rays}<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>$

4.  $\mathrm{X}-\mathrm{rays}$

A X-ray tube operates at an accelerating potential of 20 kV. Which of the following wavelength will be absent in the continuous spectrum of X-rays?

1.  12 pm

2.  75 pm

3.  65 pm

4.  95 pm

In the phenomenon of electric discharge through gases at low pressure, the coloured glow in the tube appears as a result of:

1. excitation of electrons in the atoms 

2. the collision between the atoms of the gas 

3. the collisions between the charged particles emitted from the cathode and the atoms of the gas 

4. the collision between different electrons of the atoms of the gas 

The energy of a photon of light with wavelength 5000 Å is approximately 2.5 eV. This way the energy of an X-ray photon with wavelength 1Å would be 
(1) 2.5/5000 eV             

(2) $2.5/{\left(5000\right)}^2<mspace\; width="1em"></mspace>\mathrm{eV}$

(3) $2.5\times 5000<mspace\; width="1em"></mspace>\mathrm{eV}$           

(4)  $2.5\times {\left(5000\right)}^2<mspace\; width="1em"></mspace>\mathrm{eV}$