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.
I think the correct answer is C
Look at bitesizes physics section, they have all the information you need to complete this question.
Location A receives more rainfall than Location B due to the rain shadow effect.
<u>Explanation</u>:
- Rain shadow effect is caused due to the presence of mountains.
- A rain shadow area is an area of land that has been forced to become dry, devoid of any vegetation growth due to the blockage of precipitation by mountains. These rain shadow areas will have a dry climate.
- The other side of the mountain would receive plenty of precipitation and therefore would be flourished with plant growth. These areas will have a cool and wet climate.
- In this case, Location A is on the other side of the mountain and so receives more rainfall or precipitation. Meanwhile, Location B is on the rain shadow region and so receives less rainfall.
It is a completely false statement that in <span>any energy transformation, there is always some energy that gets wasted as non-useful heat. The correct option among the two options that are given in the question is the second option. I hope that this is the answer that has actually come to your desired help.</span>
