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For anallactic lens in D = Ks + C, which of the following is zero?

For anallactic lens in D = Ks + C, which of the following is zero? Correct Answer C

The constant C is equal to (f + c). It is called additive constant whose value ranges from 30 cm to 50 cm for external focusing telescopes and 10 cm to 20 cm for internal focusing telescopes. For telescopes fitted with anallactic lens, C equals zero.

Related Questions

 Which of the following statements is/are true of the human eye lens? Choose the correct answer from the code given below:  (i) It is a convex lens (ii) It is a concave lens (iii) It is a convex lens of variable focal length (iv) It forms a real and inverted image of a distant object at the retina
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1. Ciliary muscles attached to the lens
flatten it for distant objects
2. Ciliary muscles attached to the lens thicken for closer objects
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4. Ciliary muscles thicken the lens for distant objects
Select the correct answer from the options given below:
The following are the staff readings given when the staff is held normal. The line of sight of instrument is placed at an angle +3024ꞌ. It being an anallactic lens, find the horizontal distance between staff and instrument station. Staff readings – 2.145 m, 1.925 m, 1.464 m.
The following notes refer to a traverse run by a tacheometer fitted with an anallactic lens, with constant 100 and staff held vertical. Line, Bearing, Vertical Angle, Staff Intercept -PQ, 30o 24′, + 5o 06′,1.875; QR, 300o 48′, + 3o 48′,1.445; RS, 226o 12′, − 2o 36′, 1.725 respectively. Find the length and bearing of SP.
Usage of anallactic lens makes the entire process more simple and reliable.
What is the value of additive constant in anallactic lens?
Calculate the value of R.L for staff being vertical and possessing staff readings as follows 2.892, 2.234, 1.926. It being an anallactic lens possesses an instrumental height of 1.94 with R.L 102.34 m. Line of sight placed at an angle of 2042ꞌ.
Consider the following statement: A ray of light passing through the optical centre of a convex lens emerges without any deviation after refraction. A ray of light passing through the first principal focus of a convex lens  emerges parallel to the principal axis after refraction. A ray of light passing through the optical centre of a convex lens emerges parallel to the principal axis after refraction. Which one of the following statements INCORRECT?