# Physics Entry Tests MCQs With Answers Solutions

If you are looking objective type MCQs of Physics for upcoming tests for entrance exams tests you are here on right page. Learn objective type MCQs online quiz tests for Physics Competitive exams Preparations with past papers of online quizzes.

#### Physics Solved MCQs Online Quiz Test

Q.1: When X-rays are passed through successive aluminum sheets what happens to their thickness ?

1. increases
2. it decreases
3. it remains same
4. sometimes increases and sometimes decreases

C

Q.2: Quality of X-rays depends upon —— A-filament current B-accelerating voltage C-material of the target ?

1. A And B
2. B And C
3. A And C
4. A B And C

B

Q.3: In an X-ray tube electrons each of charge e are accelerated through V potential difference allowed to hit a metal target. The wavelength of the X-rays emitted is——–?

1. he/ev
2. he/Vc
3. eV/h
4. impossible to predict

A

Q.4: Radiation produced from TV picture tube is——-?

1. B-rays
2. X-rays
3. Far infrared
4. Infrared

B

Q.5: The minimum wavelength of X-rays can further be reduced by ——–?

1. Reducing the pressure or cooling the target
2. Increasing the temperature of the filament.
3. Using a target element of higher atomic number
4. Increasing the potential difference between the cathode and the target

D

Q.6: The characteristic X-rays spectrum is due to——-?

1. The illumination of the target metal by ultra-violet radiation
2. The bombardment of the target by protons
3. The bombardment of target by electrons
4. The absorption of radiation by the target metal

C

Q.7: The minimum wavelength of X-rays produced by the bombardment of electrons on the screen of a television set where the accelerating potential is 2.0K V will be——-?

1. 6.2 x 10-10m
2. 9.1 x 10-18m
3. 3.11 x 10-10m
4. 4 x 10-10m

A

Q.8: Maximum frequency in the spectrum from X-ray tube is directly proportional to the——-?

1. Number of incident electron i.e. filament current
2. The kinetic energy of the incident electron i.e. the potential difference through which they are accelerated
3. The soft target which can easily emit electrons
4. All of above are correct

B

Q.9: X-rays are diffracted by a crystal but not by a diffraction grating because——-?

1. The ions in a crystal are well arranged
2. The lines in a diffraction grating cannot reflect X-rays.
3. The penetration power of X-rays is high in a diffraction grating
4. The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal

D

Q.10: UV radiation can be produced by——-?

1. Heating the filament
2. Electron excitation in the gas
3. Ionization of atoms
4. All the above

B