Answer:
soundproofing or absorbing
Explanation:
Acoustics is the study of waves, vibrations and sound and its most common applications lie in the sound and noise control industries. Acoustic protection is the application of soft and porous material to protect individuals against undesirable sounds and noises.
cushioned seats and carpeted floors are used in soundproofing to block the unwanted noise and sound.
The Cheapest Ways To Soundproof A Room
1. Rugs:
Rugs make excellent vibration dampeners.
2. Weather Stripping:
If you know that sound is getting into your room via the door or the windows then a very cheap and effective solution can be to use weather stripping.
3. Blankets.
4. Curtains.
5. Egg Cartons.
Homemade Soundproofing Panels
Answer:
Series circuit:
The voltage that is measured across the circuit is different.
The current measured in a series circuit remains the same at all points in the circuit.
Parallel circuit:
The current measured across each resistor varies
The voltage measured across a parallel circuit will remain the same
Explanation:
Series and parallel circuits behave differently when it comes to the circulation of current and the interaction with a potential difference.
In a series circuit, the resistances are connected end to end. As a result, the voltage that is measured across the circuit is different once resistance is encountered. However, the current measured in a series circuit remains the same at all points in the circuit.
A parallel circuit behaves in an exactly opposite manner to the series circuit. In a parallel circuit, the resistances are connected side by side. As a result of this, the current measured across each resistor varies as there are circuit branches through which electric current can flow into. On the other hand, the voltage measured across a parallel circuit will remain the same
First,
where 
is density, 
is mass, and 
is volume. We can compute the volume of the roll:
When the roll is unfurled, the aluminum will be a rectangular box (a very thin one), so its volume will be the product of the given area and its thickness 
. Note that we're assuming the given area is not the actual total surface area of the aluminum box, but just the area of the largest face (i.e. the area of one side of the unrolled sheet of aluminum).
So we have
where 
is the given area, so
If we're taking significant digits into account, the volume we found would have been 
, in turn making the thickness 
.
CORRECT ANSWER:
d. Anywhere from days to thousands of years.
STEP-BY-STEP EXPLANATION:
The whole question from book is
How long do molecules of groundwater stay in the
ground?
a. Days
b. Weeks
c. Months
d. Anywhere from days to thousands of years
The question is incomplete. You dis not provide values for A and B. Here is the complete question
Light in the air is incident at an angle to a surface of (12.0 + A) degrees on a piece of glass with an index of refraction of (1.10 + (B/100)). What is the angle between the surface and the light ray once in the glass? Give your answer in degrees and rounded to three significant figures.
A = 12
B = 18
Answer:
18.5⁰
Explanation:
Angle of incidence i = 12.0 + A
A = 12
= 12.0 + 12
= 14
Refractive index u = 1.10 + B/100
= 1.10 + 18/100
= 1.10 + 0.18
= 1.28
We then find the angle of refraction index u
u = sine i / sin r
u = sine24/sinr
1.28 = sine 24 / sine r
1.28Sine r = sin24
1.28 sine r = 0.4067
Sine r = 0.4067/1.28
r = sine^-1(0.317)
r = 18.481
= 18.5⁰
