Answer:
Amplitude is decreased by a factor of 
if intensity is decreased by a factor of 3.
Explanation:
Intensity of a sound wave is directly proportional to the square of its amplitude.
Therefore, if intensity is 
and amplitude is 
, then
, where, 
is constant of proportionality.
Now, if intensity of sound wave is decreased by a factor of 3. So,
New intensity is, 
Plug in 
for . This gives,
Therefore, amplitude is decreased by a factor of .
<span>The correct answer is blue. If you look at a luminosity star chart, called the Hertzsprung Russell Diagram, you will see the measurement of luminosity on the left side, and you will see a curve of stars with different colors (which correlate to the colors of the stars). Look for 30 on the luminosity measurement (look between 1 and 100). Then, move horizontally across the diagram until you hit the stars, whose color will be blue. Thus, blue is the answer.</span>
D. Riding a bike uphill
Increased height = increased potential energy
Thank you for posting your question here at brainly. Below is the solution:
Ke up top = 1/2*.25 *225
<span>gain of Pot energy = .25*9.81*1.2 </span>
<span>work input = (1/4)(2 pi *.6)*30 </span>
<span>so </span>
<span>sum of those 3 energies = </span>
<span>(1/2)(.25)v^2</span>
