Light - Study Mode
[#136] Which of the following statements is true?
Correct Answer
(D) radius of curvature equal to twice the focal length
[#137] Raman effect' deals with the light rays passing through
Correct Answer
(D) All transparent medium
[#138] An object is placed on the principal axis of a convex lens of focal length 10 cm. If the distance of the object from the lens is 30 cm. What is the distance of the image formed?
Correct Answer
(B) 15 cm
Explanation
Solution: First, let's identify what we know: * Focal length (f) = 10 cm This tells us how strongly the lens bends light. * Object distance (u) = 30 cm This is the distance between the object and the lens. Remember to use the sign convention! For a convex lens, u is usually taken as negative. So, u = -30 cm We need to find: * Image distance (v) = ? This is the distance between the image and the lens. This is what we want to calculate. Now, let's use the lens formula: 1/f = 1/v - 1/u Plug in the values: 1/10 = 1/v - 1/(-30) 1/10 = 1/v + 1/30 Now, let's solve for 1/v: 1/v = 1/10 - 1/30 1/v = (3 - 1)/30 1/v = 2/30 1/v = 1/15 Therefore, v = 15 cm So, the correct answer is Option B: 15 cm
[#139] The optical phenomenon that is primarily responsible for the observation of rainbow on a rainy day is
Correct Answer
(C) dispersion
[#140] When an object is kept between two parallel plane mirrors then what is the number of images formed?
Correct Answer
(D) Infinite