Compared with an Earth year, a galactic year represents time on a grand scale but its not a consistent measurement across the galaxy
Answer:
330.24 Hz
Explanation:
Given:
Frequency, f = 320 Hz
L1 = 25.8 cm
L2 = 78.4 cm
L3 = 131.1 cm
Let the wavelength be λ
Then, L1 which is the length of the column of air is λ/4.
λ/4 = 25.8 cm
λ = 25.8 × 4 = 103.2 cm = 1.032 m
Then, speed of sound in air is:
v = λ f
⇒ v = 1.032 × 320 Hz
⇒ v = 330.24 m/s
The relationship between wavelength

, frequency f and speed of light c for an electromagnetic wave is

Using the data of the problem, we find
Answer:
The brightness of bulb 1 dies because it is switched off.
The speed of light to be slightly less in atmosphere then in vacuum because of absorption and re-emission of light by the atmospheric molecules occurred when light travels through a material
<u>Explanation:</u>
When light passes through atmosphere, it interacts or transmits through the transparent molecules in atmosphere. In this process of transmission through atmosphere, the light will be getting absorbed by them and some will get re-emitted or refracted depending upon wavelength.
But in vacuum the absence of any kind of particles will lead to no interaction and no energy loss, thus the speed of the light will be same in vacuum while due to interactions with molecules of atmosphere, there speed will be slightly less compared to in vacuum.