Question 1

For reproducing sound, a CD (Compact Disc) audio player uses a:

Accepted Answer

In a CD audio player, sound reproduction is achieved by scanning the digital data using a laser beam.

Question 2

Barium in a suitable form is administered to patients before an X-ray examination of the stomach, because

Accepted Answer

Barium compounds are used before stomach X-ray examinations because they effectively absorb X-rays, which helps in creating contrast for clear imaging of the stomach in comparison to other regions.

Question 3

Recently, LASIK (Laser Assisted In Situ Keratomileusis) procedure is being made popular for vision correction. Which one of the following statements in this context is-not correct?

Accepted Answer

LASIK, or Laser Assisted In Situ Keratomileusis, is a popular procedure for correcting vision. One must be at least 18 years old to undergo LASIK, as the vision of individuals younger than 18 tends to keep changing.

Question 4

The known forces on nature can be divided into four classes, viz., gravity, electromagnetism, weak nuclear force and strong nuclear force. With reference to them, which one of the following statements is not correct?

Accepted Answer

In the realm of nature, there are four distinct forces: gravity, electromagnetism, weak nuclear force, and strong nuclear force. The statement that is incorrect among these forces is that gravity is the strongest force. The correct answer is option (a).

Question 5

A new optical disc format known as the Blu-ray Disc (BD) is becoming popular. In what way is it different from the traditional DVD? 1. DVD supports Standard Definition video while BD supports high definition video 2. Compared to a DVD, the BD format has several times more storage capacity 3. Thickness of BD is 2.4 mm while that of DVD is 1.2 mm. Which of the statements given above is/are correct?

Accepted Answer

Blu-ray Discs (BD) are gaining popularity as a new optical disc format. They differ from traditional DVDs in several ways. BD supports high definition video, unlike DVDs which support Standard Definition video. Additionally, the BD format has significantly more storage capacity compared to DVDs. While the statement that the thickness of a BD is 2.4 mm is incorrect, as it is actually 1.1 mm, the thickness of a DVD is 1.2 mm. Therefore, statements 1 and 2 are correct.

Physics - Modern Physics — UPSC Previous Year Questions

For reproducing sound, a CD (Compact Disc) audio player uses a:

Year-wise Distribution

Sample Questions

Physics - Modern Physics — UPSC Previous Year Questions

For reproducing sound, a CD (Compact Disc) audio player uses a:

Year-wise Distribution

Sample Questions