Superposition

Question 1

What is the principle of superposition?

Answer 1

The resultant displacement is the algebraic sum of individual displacements where waves meet.

Question 2

What is interference?

Answer 2

The superposition of two or more waves to form a resultant wave with varying amplitude.

Question 3

What is coherence?

Answer 3

Waves having the same frequency/wavelength and constant phase difference.

Question 4

What is constructive interference?

Answer 4

Waves in phase with a path difference of nλ

Question 5

What is destructive interference?

Answer 5

Waves out of phase with a path difference of (n+½)λ

Question 6

What is the condition for constructive interference for in-phase sources?

Answer 6

Path difference = nλ

Question 7

What is the condition for destructive interference for in-phase sources?

Answer 7

Path difference = (n+½)λ

Question 8

What is two-source interference?

Answer 8

Interference pattern formed by waves from two coherent sources.

Question 9

What are the conditions for observable two-source interference?

Answer 9

Same type

Question 10

How can water wave interference be demonstrated?

Answer 10

Using ripple tanks with two ripple generators.

Question 11

How can light wave interference be demonstrated?

Answer 11

Using Young’s double-slit experiment.

Question 12

How can microwave interference be demonstrated?

Answer 12

Using two microwave emitters and a detector.

Question 13

What is a stationary wave?

Answer 13

A wave formed by the superposition of two identical waves traveling in opposite directions.

Question 14

What is a node in a stationary wave?

Answer 14

Point of destructive interference with zero amplitude.

Question 15

What is an antinode in a stationary wave?

Answer 15

Point of constructive interference with maximum amplitude.

Question 16

What is the separation between nodes or antinodes?

Answer 16

λ/2

Question 17

Do stationary waves transfer energy?

Answer 17

No

Question 18

How do particles move between two adjacent nodes?

Answer 18

In phase with each other.

Question 19

What is the phase difference between particles in adjacent sections of a stationary wave?

Answer 19

π radians

Question 20

How can stationary waves be formed on a string?

Answer 20

By reflection of waves from a fixed or weighted end.

Question 21

How can stationary microwaves be detected?

Answer 21

Using a microwave emitter and a metal reflector with a detector.

Question 22

How are stationary waves formed in air columns?

Answer 22

By sound waves reflecting at the water surface or tube ends.

Question 23

Where is the node formed in a closed air column?

Answer 23

At the surface of water (closed end).

Question 24

What is diffraction?

Answer 24

The spreading of waves as they pass through a narrow slit or around an obstacle.

Question 25

When does significant diffraction occur?

Answer 25

When the slit size is comparable to the wavelength.

Question 26

What is the double-slit interference formula?

Answer 26

λ = ax / D

Question 27

What do the symbols in λ = ax / D represent?

Answer 27

a = slit separation

Question 28

What happens if white light is used in double-slit interference?

Answer 28

Central fringe is white; others are colored due to varying λ.

Question 29

What is the diffraction grating formula?

Answer 29

dsinθ = nλ

Question 30

What does ‘d’ represent in dsinθ = nλ?

Answer 30

Distance between slits = 1 / N

Question 31

What is the main difference between double-slit and diffraction grating patterns?

Answer 31

Grating gives brighter