The one that will change the velocity of a periodic wave is :
B. Changing the medium of the wave
Waves is always determined by the properties of the medium, which means that changing the medium will change the velocity of the wave
hope this helps
Answer:
<h2>2.4</h2>
Explanation:
<h2><em>Hope it help mark as Brainlist</em></h2>
Answer:
The frequency is 302.05 Hz.
Explanation:
Given that,
Speed = 18.0 m/s
Suppose a train is traveling at 30.0 m/s relative to the ground in still air. The frequency of the note emitted by the train whistle is 262 Hz .
We need to calculate the frequency
Using formula of frequency

Where, f = frequency
v = speed of sound
= speed of passenger
= speed of source
Put the value into the formula


Hence, The frequency is 302.05 Hz.