Answer:
When the air pressure in the throat and outside the body is less than the air pressure in the middle ear, barotrauma occurs.
Explanation:
Ear barotrauma is a medical condition that describes discomfort in the ear which is caused by pressure differences in the inner and outer ear drum.
Usually, the air pressure in the middle ear is the same as the air pressure in the throat and outside the body.
When we swallow, the eustachian tube opens up and air flows out of and into the middle ear, this balances the pressure. But if the eustachian tube is blocked, the air pressure in the throat and outer body become different from the air pressure in the middle ear.
I believe the correct answer from the choices listed above is the third option. <span>The force exerted by the book on the table is equal to the force exerted by the table which is 4.0 N. The book does not move so it must be that the forces are balanced. Hope this answers the question.</span>
Recall the equation for magnetic force:
F = qv x B *x is cross product, not separate variable!
If the magnetic field points towards N and you throw E, then the magnetic force would point up, or out of the page. Use the right-hand rule. You point your finger towards the direction of the object, and curl your finger to the magnetic field. Your thumb is the direction of the magnetic force.
Hope this helps!
Answer:
9.34 N
Explanation:
First of all, we can calculate the speed of the wave in the string. This is given by the wave equation:

where
f is the frequency of the wave
is the wavelength
For the waves in this string we have:
, since it completes 625 cycles per second
is the wavelength
So the speed of the wave is

The speed of the waves in a string is related to the tension in the string by
(1)
where
T is the tension in the string
is the linear density
In this problem:
is the mass of the string
L = 0.75 m is the its length
Solving the equation (1) for T, we find the tension:

Hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh