Answer:

Explanation:
The formula that relates angular displacement with angular acceleration is:

We can obtain
from the definition of angular acceleration:


Putting all together:

Which, since we want the angular acceleration, is:

And for our values is:

<span> </span>speed<span>using the v = f. λ </span>equation<span>.</span>
Examples are, starting a car, turning on a light, cooking on an electric stove, watching tv, shaving with an electric razor, playing video games, using a phone, and charging a cell phone, i found this information on www.electricityforum.com
Answer:
The student hears the wave that is transmitted by the desk
Explanation:
Mechanical waves need a material medium to be able to be transmitted, in the case of sound waves, one of the most common media is air, but it is also transmitted in other media in this case, stationery is transmitted.
The student hears the wave that is transmitted by the desk
The speed of the wave is proportional to the density of the material, so the wave that the student hears arrives much faster through the desk than through the air