Answer:
iv) It is 9x bigger than before
Explanation:
As the amplitudes of the new speakers add directly with the original one, taking into account the phase that they have, the composed amplitude of the sound wave is as follows:
At = A + 4A -2A = 3 A
The intensity of the wave, assuming it propagates evenly in all directions, is constant at a given distance from the source, and can be expressed as follows:
I = P/A
where P= Power of the wave source, A= Area (for a point source, is equal to the surface area of a sphere of radius r, where is r is the distance to the source along a straight line)
For a sinusoidal wave, the power is proportional to the square of the amplitude, so the intensity is proportional to the square of the amplitude also.
If the amplitude changes increasing three times, the change in intensity will be proportional to the square of the change in amplitude, i.e., it will be 9 times bigger.
So, the statement iv) is the right one.
Answer:
A type of telescope that does not require darkness in order to be able to use it is the refracting telescope
Explanation:
A refracting telescope consists of a lens and an eyepiece collects light which is then focused to present a magnified, bright and clear image.
The incident light on a refracting telescope is bent by refraction such that the light is focused to the focal point.
In refracting telescopes, the image is formed by bending light, that is by refraction.
The refracting telescope technology has been applied to binoculars and camera zoom lenses.
E. Nonsense longitudinal waves have all of these properties
