Explore topic-wise MCQs in Engineering Physics.

This section includes 11 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering Physics knowledge and support exam preparation. Choose a topic below to get started.

1.

The energy levels of which ion/atom/molecule are responsible for lasing action?

A. Al3+
B. Cr3+
C. Al2O3
D. Cr2O3
Answer» C. Al2O3
2.

What is the wavelength of the emitted laser in a Ruby laser?

A. 694 nm
B. 650 nm
C. 780 nm
D. 754 nm
Answer» B. 650 nm
3.

What will be the relative population of atoms in a ruby layer that produces a light beam of wavelength 6943 Å at 300 K.

A. 5 X 10-31
B. 6 X 10-31
C. 7 X 10-31
D. 8 X 10-31
Answer» E.
4.

For a Ruby laser, the coherence time t = 10-10 s. The degree of Monochromaticity is __________

A. 0.13 X 10-4
B. 0.24 X 10-4
C. 0.35 X 10-4
D. 0.47 X 10-4
Answer» B. 0.24 X 10-4
5.

The following graph represents the output for which type of LASER?

A. He-Ne Laser
B. Ruby Laser
C. ND: YAG laser
D. Semiconductor Diode laser
Answer» C. ND: YAG laser
6.

The laser beam is emitted in the form of __________

A. Fluctuating radiations
B. Continuous spectrum
C. Pulsed output
D. Exponentially decreasing intensity
Answer» D. Exponentially decreasing intensity
7.

Which material is used for cooling of the ruby rod for efficient continuous operation?

A. CFC
B. Liquid helium
C. Liquid oxygen
D. Liquid Nitrogen
Answer» E.
8.

The pumping mechanism used in Ruby rod is __________

A. Optical Pumping
B. Electrical Excitation
C. Chemical pumping
D. Thermal pumping
Answer» B. Electrical Excitation
9.

The ends of the ruby rod works as __________

A. Pumping source
B. Active medium
C. Cavity mirrors
D. Energy levels
Answer» D. Energy levels
10.

The lifetime of meta-stable state in a Ruby laser is ___________

A. 10-8s
B. 10-6s
C. 10-3s
D. 10-2s
Answer» D. 10-2s
11.

Which of the following is a three-level laser?

A. ND: YAG
B. Ruby
C. He-Ne
D. Semiconductor laser
Answer» C. He-Ne