Here, "Wavelength is same for both waves" it is the distance between two crests or two consecutive troughs, so, it is constant for both of them, you can easily figure it out.
In short, Your Answer would be "Wavelength"
Hope this helps!
The second option rolling friction
Answer:
<em>2.78m/s²</em>
Explanation:
Complete question:
<em>A box is placed on a 30° frictionless incline. What is the acceleration of the box as it slides down the incline when the co-efficient of friction is 0.25?</em>
According to Newton's second law of motion:

Where:
is the coefficient of friction
g is the acceleration due to gravity
Fm is the moving force acting on the body
Ff is the frictional force
m is the mass of the box
a is the acceleration'
Given

Required
acceleration of the box
Substitute the given parameters into the resulting expression above:
Recall that:

9.8sin30 - 0.25(9.8)cos30 = ax
9.8(0.5) - 0.25(9.8)(0.866) = ax
4.9 - 2.1217 = ax
ax = 2.78m/s²
<em>Hence the acceleration of the box as it slides down the incline is 2.78m/s²</em>
Answer:
Noise cancelling headphones have a microphone which listens to the ambient noise. The headphone then processes the sound and provides a wave to produce destructive interference. This cancels the ambient noise.
Explanation:
First, let us understand what interference is. Interference is the phenomenon that occurs when two waves superpose to form a wave which has a different wavelength, frequency, amplitude than the original two waves. When the crest of one wave superposes with the other waves crest then this results in the amplitude increasing. This is known as constructive interference. When the crest of one wave superposes with the other waves trough then this results in the amplitude decreasing. This known as destructive interference.
Noise cancelling headphones have a microphone which listens to the ambient noise. The headphone then processes the sound and provides a wave to produce destructive interference. This cancels the ambient noise.