This question is incomplete, the complete question is;
When an auditorium has a solid wall, sound waves will tend to perfectly reflect off the wall (i.e. with a 180o phase change). If listening to music, as from an orchestra, the incoming and reflected waves will interfere with each other. For a listener sitting 0.5 m from the wall, what is the lowest frequency which gets suppressed by this interference? Use vsound=330 m/s.
Answer: f = 165 Hz
the lowest frequency which gets suppressed by this interference is 165 Hz
Explanation:
For a reflected wave (out of phase), the path difference between the incoming and reflected wave should be equal to the half integral multiple of wavelength.
r₂ - r₁ = ( m + 1/2) λ/2
r₂ is the distance from the source to observer via reflection
r₁ is distance from source to observer
here r₂ would travel an additional distance of 0.5 m due to reflection that straight approaching wave.
Therefor to have minimum/lowest possible frequency, we say m = 0
we substitute
0.5 = ( 0 + 1/2 ) λ/2
λ = 2m
The frequency would be
f = Vsound / λ
f = 330 / 2
f = 165 Hz
Therefore the lowest frequency which gets suppressed by this interference is 165 Hz
The answer is equal and opposite forces.
Answer:
F=507.7N
Explanation:
According to Newton's second law:
in this case, the football players need to drag the coach at a constant velocity, thus means with no acceleration, so:
there are 20 degrees between the two ropes that means each player exerts a force 10 degrees from the zero reference.
(a) 154.5 N
Let's divide the motion of the sprinter in two parts:
- In the first part, he starts with velocity u = 0 and accelerates with constant acceleration for a total time During this part of the motion, he covers a distance equal to , until he finally reaches a velocity of . We can use the following suvat equation:
which reduces to
(1)
since u = 0.
- In the second part, he continues with constant speed , covering a distance of in a time . This part of the motion is a uniform motion, so we can use the equation
(2)
We also know that the total time is 10.0 s, so
Therefore substituting into the 2nd equation
From eq.(1) we find
(3)
And substituting into (2)
Solving for t,
So from (3) we find the acceleration in the first phase:
And so the average force exerted on the sprinter is
b) 14.5 m/s
The speed of the sprinter remains constant during the last 55 m of motion, so we can just use the suvat equation
where we have
u = 0
is the acceleration
is the time of the first part
Solving the equation,
Answer:
I think it is the Federal Pell Grant Program.
Explanation: