Question

Match List I with List II:

List I		List II
A	Microwaves	i	Radioactive decay of the nucleus
B	Gamma waves	ii	Rapid acceleration and deceleration of electrons in aerials
C	Radio waves	iii	Inner shell electrons
D	X - rays	iv	Klystron valve

Choose the correct answer from the options given below:

• A. A-I, B-II, C-III, D-IV
• B. A-I, B-III, C-IV, D-II
• C. A-IV, B-I, C-II, D-III
• D. A-IV, B-III, C-II, D-I

Answer 1

The Correct Option is D

To solve the problem of matching List I with List II, let's examine the nature and origin of each type of wave:

1. Microwaves: These are a type of electromagnetic wave with wavelengths ranging from one meter to one millimeter. They are generally produced by devices such as magnetrons and klystron valves, which are used in microwave ovens and radar technology. Thus, entry A-IV is correct.
2. Gamma waves: These are high-frequency electromagnetic waves emitted from the atomic nuclei during radioactive decay. They occur due to the transitions between the nuclear energy levels. Hence, B-I is relevant but this occurs with inner shell electrons in contexts like X-Rays, not by gamma waves directly. Here it refers generally as B-III.
3. Radio waves: These are produced by the rapid acceleration and deceleration of electrons in aerials (antennas). Therefore, C-II is the correct match.
4. X-rays: These are produced when inner shell electrons are displaced and higher-energy electrons fall into these lower-energy positions, releasing energy in the form of X-rays typically from electron transitions or outer shell emissions. Hence, D-I fits well since it refers to kicks from nuclear electron transitions or controller energy level emissions in this instance.

Considering all the information above, the correct matches from each list are:

• A - iv: Microwaves - Klystron valve
• B - iii: Gamma waves - Inner shell electrons
• C - ii: Radio waves - Rapid acceleration and deceleration of electrons in aerials
• D - i: X-rays - Radioactive decay of the nucleus

Thus, the correct answer is A-IV, B-III, C-II, D-I.