mPEC Forum

ฟิสิกส์โอลิมปิก วิทยาศาสตร์โอลิมปิก ข้อสอบแข่งขัน ข้อสอบชิงทุน => GRE - Physics => Topic started by: conantee on January 04, 2010, 04:42:15 AM



Title: GR8677.058
Post by: conantee on January 04, 2010, 04:42:15 AM
58. In an ordinary hologram, coherent monochromatic light produces a 3-dimensional picture because wave information is recorded for which of the following?
I. Amplitude
II. Phase
III. Wave-front angular frequency
(A) I only
(B) I and II only
(C) I and III only
(D) II and III only
(E) I, II, and III


Title: Re: GR8677.058
Post by: conantee on October 11, 2010, 10:51:51 AM
This is a rare type of questions in GRE. This question sounds very technical. However, if you pay attention to the word "monochromatic", you can guess that angular frequency does not contain any information since it has only one value. The relevant choices are now (A) and (B).

The correct answer is actually (B). Phase is also recorded in order to do hologram. 45 of 100 people answer this question correctly.