Multiple Choice Questions (MCQ)
1. The shortest wavelength present in the X-rays produced at an accelerating
potential of 45 kV is:
(a) 0.276 Å
(b) 1.276 Å
(c) 2.276 Å
(d) 3.276 Å
2. The frequency corresponding to the wavelength present in the X-rays produced
at an accelerating potential of 45 kV is:
(a) 1.08 Â 10
16 Hz
(b) 1.08 Â 10
17 Hz
(c) 1.08 Â 10
18 Hz
(d) 1.08 Â 10
19 Hz
3. The potential difference across an X-ray tube is 40 kV and the current passing
through it is 30 mA, the number of electrons striking the target per second will be:
(a) 1.87 Â 10
16 /s
(b) 1.87 Â 10
17 /s
(c) 1.87 Â 10
18 /s
(d) 1.87 Â 10
19 /s
4. The potential difference across an X-ray tube is 40 kV and the current passing
through it is 30 mA, the speed at which the electrons will strike the target will
be:
(a) 1.19 Â 10
6 m/s
(b) 1.19 Â 10
7 m/s
(c) 1.19 Â 10
8 m/s
(d) 1.19 Â 10
9 m/s
5. The potential difference across an X-ray tube is 40 kV and the current passing
through it is 30 mA, the minimum wavelength of the X-ray produced will be:
(a) 0.311 Å
(b) 1.311 Å
(c) 2.311 Å
(d) 3.311 Å
6. Electrons bombarding the anode of a Coolidge tube produce X-rays of wavelength 1 Å. The energy of each electron at the time of impact is:
(a) 1.24 Â 10
3 eV
(b) 1.24 Â 10
4 eV
(c) 1.24 Â 10
5 eV
(d) 1.24 Â 10
6 eV
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7 Diffraction of Waves and Particles by Crystal