Bissoy.com
Doctors Medicines MCQs Q&A

A ruby laser has a crystal of length 3 cm with a refractive index of 1.60, wavelength 0.43 μm. Determine the number of longitudinal modes.

A ruby laser has a crystal of length 3 cm with a refractive index of 1.60, wavelength 0.43 μm. Determine the number of longitudinal modes. Correct Answer 2.2×105

The number of longitudinal modes is given by- q = 2nL/λ Where q = Number of longitudinal modes n = Refractive index L = Length of the crystal λ = Peak emission wavelength.

Related Questions

Choose the correct relation for a combination of two prisms to be achromatic. (Where for the first prism: μv = refractive index of the medium in violet light, μr = refractive index of the medium in red light A = angle of the prism; For the second prism: μ′v = refractive index of the medium in violet light, μ′r = refractive index of the medium in red light, A’ = angle of prism.)
When the refractive index $$\mu $$ of the active medium changes by $${\Delta \mu }$$  in a laser resonator of length L, the change in the spectral spacing between the longitudinal modes of the laser is (c is the speed of light in free space)
Children are in pursuit of a dog whose leash has broken. James is directly behind the dog. Ruby is behind James. Rachel is behind Ruby. Max is ahead of the dog walking down the street in the opposite direction. As the children and dog pass, Max turns around and joins the pursuit. He runs in behind Ruby. James runs faster and is alongside the dog on the left. Ruby runs faster and is alongside the dog on the right. Which child is directly behind the dog?
A semiconductor laser crystal of length 5 cm, refractive index 1.8 is used as an optical source. Determine the frequency separation of the modes.
A 4 km optical link consists of multimode step index fiber with core refractive index of 1.3 and a relative refractive index difference of 1%. Find the delay difference between the slowest and fastest modes at the fiber output.
A multimode step-index fiber has a core refractive index of 1.5 and relative refractive index difference of 1%. The length of the optical link is 6 km. Estimate the RMS pulse broadening due to intermodal dispersion on the link.
Ruby's height is 5'2". Ana is taller than Ruby but she is not taller than Pamela. Pamela is shorter than her cousin Rony but she is not shorter than Ruby. Who is the tallest in the group?
In the following question below some statements are given followed by some conclusions. Taking the given statements to be true even if they seem to be at variance from commonly known facts, read all the conclusions, and then decide which of the given conclusions logically follows the given statements. Statements: Some pink are ruby. Some pink are garnet. Conclusions: I. Some garnets are ruby.  II. All garnets are ruby.
The value of a ruby varies directly as the square of its weight. One such ruby breaks and the weight of its pieces is in the ratio of 2 ∶ 3 ∶ 4. If damage due to breakdown is Rs. 26,000, what was the cost of the original ruby?
When light passes from air to glass it experience change in refractive index. and due to change in refractive index the wavelength of light changes and hence speed.