Answer:
β = 114 db
Explanation:
The intensity of sound in decibles is
β = 10 log [tex]\frac{I}{I_{o}}[/tex]
in most cases Io is the hearing threshold 1 10-12 W / cm²
let's calculate the intensity of each instrument
I / I₀ = 10 (β / 10)
I = I₀ 10 (β / 10)
trumpet
I1 = 1 10⁻¹² 10 (94/10)
I1 = 2.51 10⁻³ / cm²
Thrombus
I2 = 1 10⁻¹² 10 (107/10)
I2 = 5.01 10-2 W / cm²
low
I3 =1 1-12 (113/10) W/cm²
I3 = 1,995 10-1 W / cm²
when we place the three instruments together their sounds reinforce
I_total = I₁ + I₂ + I₃
I_ttoal = 2.51 10-3 + 5.01 10-2 + 1.995 10-1
I_total = 0.00251 + 0.0501 + 0.1995
I_total = 0.25211 W / cm²
let's bring this amount to the SI system
β = 10 log (0.25211 / 1 10⁻¹²)
β = 114 db
Multiply.
(2x + 4)(x - 4)
Answer:
(2x + 4)(x - 4)=2x^2-4x-16
100 points!! word bank!
⬇️Article⬇️
Have you ever cut an apple in half and looked at the layers inside? When you cut something in half, the resulting view is called a cross section. When you look at the cross section of an apple, you see several layers: the skin, the pulp, the core, and the seeds. Much like the apple, Earth is made up of layers, too. If you could look at a cross section of our planet, you would see the crust. the mantle, the outer core, and the inner core. If Earth were an apple, the crust would be the apple’s skin. The mantle would be the apple’s pulp, making up most of the inside. Earth also has a central core, similar to an apple’s core, though Earth’s core does not contain any seeds! Of course, scientists cannot cut the whole planet in half to see a cross section the way you can with an apple. How do you think scientists know about Earth’s internal layers?
Scientists divide Earth’s interior into distinct layers.
Scientists can distinguish different layers in Earth depending on the properties used to identify each layer. For example, scientists identify the crust, mantle, and core based on each layer’s basic chemical composition. In other words, the crust, mantle, and core are each made up of different chemical elements. The crust and mantle are composed primarily of the elements oxygen and silicon. These are known as silicates. Silicates of the mantle contain heavier elements. This makes them denser than those found in the crust. The core is composed of the densest materials, primarily iron and nickel. Earth’s layers can also be identified by using each layer’s physical state of matter. The crust and the uppermost part of the mantle, together, make up a layer called the lithosphere. The lithosphere is the cool, rigid, outermost layer of Earth. The lithosphere is in the solid
In a typical silicate molecule, a silicon atom is bonded to four oxygen atoms. The atoms form a crystal structure.
Scientists use models to represent the different layers of Earth’s interior.
When constructing a model of the layers of Earth, scientists need to consider the chemical composition, state of matter, and thickness of each layer. Just like the skin of an apple, Earth’s crust is very thin compared to the other layers. It is about 25–70 km thick beneath the continents. Under the oceans, the crust is only about 5–7 km thick; however, it is much denser. The mantle is much thicker than the crust is, taking up most of Earth’s volume. The mantle begins directly beneath Earth’s crust. It reaches all the way to the outer core, about 2,900 km below the planet’s surface. In other words, Earth is about 1% crust, 83% mantle, and 16% core.
The crust and uppermost mantle are solid. The rest of the mantle is solid with plasticity. The core is made of very dense iron and nickel. The outer core is liquid, because it is hot enough to melt the iron and nickel. The inner core is solid. Even though it is as hot as the outer core, there is so much pressure at the very center of Earth that the iron and nickel stay in a solid state.
Looking to the Future: Exploring Earth’s Interior
Despite what you may have read in stories or seen in movies, scientists have never journeyed to the center of Earth. In fact, scientists have never made it through Earth’s crust! However, this has not stopped them from trying. The crust at the bottom of the oceans is much thinner than the crust of the continents. Therefore, drilling through the oceanic crust is the best chance that scientists have to make it to the mantle.
Answer:
Except in the crust, the interior of the Earth cannot be studied by drilling holes to take samples. Instead, scientists map the interior by watching how seismic waves from earthquakes are bent, reflected, sped up, or delayed by the various layers.
Explanation:
a consequence of "yoyo" dieting is that
Answer:
srry i ll get back to with an answer
Explanation:
What energy transformation takes place in the
solar panel?
The motion of a nightingale's wingtips can be modeled as simple harmonic motion. In one study, the tips of a bird's wings were found to move up and down with an amplitude of 8.0 cm and a period of 0.80 s.
Part A: What is the wingtips' maximum speed?
Part B: What is the wingtips' maximum acceleration?
Answer:
PART A: Maximum speed = 0.314 m/s
PART B: Maximum acceleration = 1.23 m/s²
Explanation:
A simple Harmonic motion is a repetitive motion through an equilibrium point.
Amplitude = 8.0cm = 8/100 = 0.08m (highest displacement)
period (T) = 0.80s
A) maximum speed [tex](V_{max)[/tex]
[tex]V_{max} = 2\pi fA\\where:\\A = Amplitude = 0.08m\\f = frequency = \frac{1}{period(T)} = \frac{1}{0.8} = 1.25 Hz\\\therefore 2\pi fA = 2\pi \times 1.25 \times 0.08\\= 0.314\ m/s[/tex]
B) maximum acceleration [tex](a_{max})[/tex]
[tex]a_{max} = (2\pi f)^2A\\where:\\f = 1.25Hz\\A = 0.08m\\a_{max} = (2\pi \times 1.25)^2 \times 0.08\\= 1.23\ m/s^2[/tex]
which model best represents a pattern
Answer:
A
Explanation:
What best describes the speed of light waves in solids, liquids, and gases?
The speed is fastest in solids.
The speed is fastest in liquids.
The speed is fastest in gases.
The speed is the same in all matter.
Answer: It’s fastest in gases. Letter C !
Explanation:
Answer:
its c
Explanation:
why is it difficult to lift out the bucket form well
because of gravitional pull
Need help ASAP plz and thank you!!
Answer: Possibly b
Explanation:
A particle starts from rest and moves with a constant acceleration. It travels the first 16 m in 4 s.
The time (in second) at which the velocity of the particle becomes. 8. m/s is:
a) 3
b) 4
c) 5
d) 6
e) 7
Answer:
B
Explanation:
If you add a light bulb to the circuit, the filament in the bulb will resist the flow of
electrons and convert energy into____and_____
a.)light and heat
b.)electrons and neutrons
c.)energy and matter
d.)electrons and protons
Answer:
Light and heat!
Explanation:
This is correct<3
Answer:
light and heat
Explanation:
i love science
1. express the following in proper SI form using the appropriate prefixes. a. 52500000 m b. 1000 g c. 2435200000
Answer:
a
[tex]L = 5.25*10^{7} \ m[/tex]
b
[tex]m = 1 \ kg[/tex]
c
[tex]t = 1.46112000000 *10^{11} \ s[/tex]
Explanation:
From the question we are told that
Length is L = 52500000 m
Mass is
Time is 2435200000 minutes
Generally the proper SI for length is meters ,
Now converting the given length to proper SI form using the appropriate prefixes we have that
[tex]L = 5.25*10^{7} \ m[/tex]
Generally the proper SI for mass is kilograms
converting grams to kilograms , we have
[tex]m =\frac{1000}{1000 }[/tex]
=> [tex]m = 1 \ kg[/tex]
Generally the proper SI for time is seconds
converting minutes to seconds , we have
[tex]t = 24352000000* 60[/tex]
=> [tex]t = 146112000000 \ s[/tex]
Now converting to the proper SI form using the appropriate prefixes
[tex]t = 1.46112000000 *10^{11} \ s[/tex]
Two spheres of equal mass, A and B, are projected off the edge of a 1.0 m bench. Sphere A has a horizontal velocity of 10 m/s and sphere B has a horizontal velocity of 5 m/s.
__ 5. If both spheres leave the edge of the table at the same instant, sphere A will land
a. at some time after sphere B.
b. at the same time as sphere B.
c. at some time before sphere B.
d. There is not enough information to decide.
__ 6. If both spheres leave the edge of the table at the same instant, sphere A hits the floor at the spot marked X. Sphere B will hit the floor
a. at some point between the edge of the table and X.
b. at some point past X.
c. at the same distance from the table as X.
d. there is not enough information to decide.
Answer:
c. because A will land first becuase its heavier
and D.
Explanation:
A certain electrical circuit contains a battery with three cells, wires, and a light bulb. Which of the following would cause the bulb to shine less brightly?
A. decrease the resistance of the circuit
B. increase the resistance of the circuit
An axe used to split wood is driven into a piece of wood for an input distance of 0.05m. If the mechanical
advantage of the axe is 0.85, how far apart (output distance) is the wood split?
A convex mirror has a focal length of -12 cm. A lightbulb with
a diameter of 6.0 cm is placed 60.0 cm in front of the mirror.
Locate the image of the lightbulb. What is its diameter?
Answer:
PLEASE MARK AS BRAINLIEST!!
Explanation:
ANSWER IS IN THE IMG BELOW
A 100 kg gymnast comes to a stop after tumbling. Her feet do 5,000 J of work to stop her.
Which of the following was the girl's velocity when she began to stop?
Answer:10 m/s
Explanation:
A 100 kg gymnast comes to a stop after tumbling. Her feet do 5,000 J of work to stop her. The girl's velocity when she began to stop is 10 m/sec.
What is velocity?When an item is moving, its velocity is the rate at which its direction is changing as seen from a certain point of view and as measured by a specific unit of time. Velocity is vector quantity.
Uniform motion an object is said to have uniform motion when object cover equal distance in equal interval of time within exact fixed direction. For a body in uniform motion, the magnitude of its velocity remains constant over time. Here in the question velocity is changing by using work energy theorem we have,
work done = change in kinetic energy
5000 = (.5).m.v² , where v is velocity.
5000 = (.5).100.v²
v = 10 m/sec
A 100 kg gymnast comes to a stop after tumbling. Her feet do 5,000 J of work to stop her. The girl's velocity when she began to stop is 10 m/sec.
To learn more about velocity refer the link:
brainly.com/question/18084516
#SPJ6
Explain
applications
MRI
X-ray
Ultrasound
Infrared Radiation
Answer and Explanation:
--> MRI (Magnetic Resonance Imaging) is an imaging technique that involves the use of radio waves and magnetic field to generate high detailed images of the human body. It's clinical applications includes:
• Bone and joint MRI: these are done to check for bone and joint problems such as bone marrow disorders, arthritis, or bone tumours.
• A Spine MRI: This is used to investigate the spinal disc and innervations for disorders such as spinal tumours.
• Chest MRI: This is used to detect abnormalities of the heart, heart valves and coronary arteries.
--> X-RAY: These are electromagnetic waves of short wavelength with high penetrating power. They are produced when fast moving electrons strike a mass of heavy atoms such as those of metals. It's applications includes:
• They are used to detect hidden cracks in materials.
• They are used to show broken bones in human body.
• They are used in the study of internal structures of crystals.
• In agriculture, x-rays are used in killing germs.
--> ULTRASOUND: This makes use of high frequency sounds to detect abnormalities in the human body. An ultrasound machine transmits sound waves into the body which are reflected at the surfaces between the tissues of different density. It can also be used in different disciplines such as imaging, cleaning, mixing, navigation and communication It's applications includes:
•. Detection of Cracks: when applied on metallic surface under investigation, high frequency sound wave reflects back which and be predicted and recorded.
--> INFRARED RADIATION: This is a type of electromagnetic radiation with wavelength longer than visible light. It is visible to the human eye and most heated surfaces transmits infrared radiation. It's applications includes:
• it is used for the purpose of sensing and detection. For example the night vision goggles and infrared cameras. Remote control makes use of infrared light waves to change channels in the television.
A bowling ball weighing 71.2 N is swinging like a pendulum at the end of a 3.8 m rope. As the ball swings through its lowest point, its speed is measured at 4.2 m/s. What is the magnitude and direction of the acceleration of the ball at this point?
At its lowest point, the ball feels a downward force due to its weight of 71.2 N and an upward force of tension from the rope. Its motion is circular, so that the net radial acceleration is felt upward toward the center of the circle.
With a tangential speed of 4.2 m/s at the lowest point, its radial acceleration has magnitude
a = (4.2 m/s)² / (3.8 m) ≈ 4.6 m/s²
Why when i take "The FitnessGram Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. A single lap should be completed each time you hear this sound. Remember to run in a straight line, and run as long as possible." i don't fall flat on my face?
Answer:
NOOOOOOO NOT THE PACER TEST!!
Explanation:
MEMORIES OF MIDDLE SCHOOL I'D LIKE TO FORGET
also. LOL "Remember to run in a straight line" BRUH WE KNOW XDXD
Where are you atera11
Answer:
? who is atera11?
Explanation:
two spheres A and B are projected off the edge of a 1.0 m high table with the same horizontal velocity . sphere A has a mass of 20.g and sphere B has a mass of 10.g.
If both spheres leave the edge of the table at the same instant, sphere A will land
a. at some time after sphere B.
b. at the same time as sphere B.
c. at some time before sphere B.
d. There is not enough information to decide.
__ 6. If both spheres leave the edge of the table at the same instant, sphere A hits the floor at the spot marked X. Sphere B will hit the floor
a. at some point between the edge of the table and X.
b. at some point past X.
c. at the same distance from the table as X.
d. there is not enough information to decide.
Answer:
C. and D.
C. becuase A is heavier so it will land first
Can hurricanes produce tornadoes
Answer:
No
Explanation:
Answer:
No
Explanation:
Tornadoes are usally produced in the Midwest regions. Hurricanes are made with water, not clouds. So, no, hurricanes cannot produce tornadoes.
Ishan is testing materials to see whether they will stick to a magnet. How can
he use his imagination in this experiment?
OA. To think of different materials to test
OB. To carefully record the results in a chart
O C. To do the test the same way each time
O D. To remember which materials are magnetic
Answer:
The Answer is A "To think of different materials to test"
Explanation:
APE X
A 1kg dictionary is resting on a table that is 1.5m high. How much potential energy
does it have?
Answer:
Potential energy = 14.7 Joules.
Explanation:
Given the following data;
Mass, m = 1kg
Height, h = 1.5m
We know that acceleration due to gravity is equal to 9.8m/s²
Potential energy can be defined as an energy possessed by an object or body due to its position.
Mathematically, potential energy is given by the formula;
[tex] P.E = mgh[/tex]
Where, P.E represents potential energy measured in Joules.
m represents the mass of an object.
g represents acceleration due to gravity measured in meters per seconds square.
h represents the height measured in meters.
[tex] P.E = mgh[/tex]
Substituting into the equation, we have;
[tex] P.E = 1*9.8*1.5[/tex]
P.E = 14.7 Joules.
how would you write 4.3756 in standard decimal form
A thin, uniform stick of mass M and length L is at rest on a flat, frictionless surface to which one end of it is pinned. A small mass m traveling at speed v collides with and attaches to the stick at a distance 2L/3 away from the end through which it is pinned to the surface. (a) Find an expression for the moment of inertia of the stick mass object after the collision. (b) Find an expression for the final angular speed of the combined object
Answer:
a) I = ([tex]\frac{M}{3}[/tex] + [tex]\frac{4m}{9}[/tex]) L² , b) w = (\frac{27 M}{18 m} + 2)⁻¹ Lv₀
Explanation:
a) The moment of inertia is a scalar that represents the inertia in circular motion, therefore it is an additive quantity.
The moment of inertia of a rod held at one end is
I₁ = 1/3 M L²
The moment of inertia of the mass at y = L
I₂ = m y²
The total inertia method
I = I₁ + I₂
I = \frac{1}{3} M L² + m (\frac{2}{3} L)²
I = ([tex]\frac{M}{3}[/tex] +[tex]\frac{4m}{9}[/tex] ) L²
b) The conservation of angular momentum, where the system is formed by the masses and the bar, in such a way that all the forces during the collision are internal.
Initial instant. Before the crash
L₀ = I₂ w₀
angular and linear velocity are related
w₀ = y v₀
w₀ = [tex]\frac{2}{3}[/tex]L v₀
L₀ = I₂ y v₀
Final moment. After the crash
[tex]L_{f}[/tex] = I w
how angular momentum is conserved
L₀ = L_{f}
I₂ y v₀ = I w
substitute
m ([tex]\frac{2L}{3}[/tex])² (\frac{2L}{3} v₀ = ([tex]\frac{M}{3}[/tex] +[tex]\frac{4m}{9}[/tex] ) L² w
[tex]\frac{6}{27}[/tex] m L³ v₀ = ([tex]\frac{M}{3}[/tex] +[tex]\frac{4m}{9}[/tex] ) L² w
[tex]\frac{6}{27}[/tex] m L v₀ = ([tex]\frac{M}{3}[/tex] +[tex]\frac{4m}{9}[/tex] ) w
L v₀ = [tex](\frac{27 M}{18 m} + 2)[/tex] w
w = (\frac{27 M}{18 m} + 2)⁻¹ Lv₀
Which of the following examples best represents an object with balanced forces acting upon it?
A - A boat accelerating through the water.
B - A book sitting at rest on a high shelf.
C- A wagon rolling down a steep hill.
D- A baseball thrown into the air.
Answer:the answer is “A book sitting on a high shelf” :)
Explanation:
A block with a mass of 0.30 kg is attached to a horizontal spring. The block is pulled back from its equilibrium position until the spring exerts a force of 1.2 N on the block. When the block is released, it oscillates with a frequency of 1.1 Hz.
How far was the block pulled back before being released?
Answer:
The value is [tex]x = 0.084 \ m[/tex]
Explanation:
From the question we are told that
The mass of the block is [tex]m = 0.30 \ kg[/tex]
The force exerted is [tex]F = 1.2 \ N[/tex]
The frequency is [tex]f = 1.1 \ Hz[/tex]
Generally the spring constant of the spring is mathematically represented as
[tex]k = (2 \pi f)^2 * m[/tex]
=> [tex]k = (2 * 3.142 * 1.1 )^2 * 0.30[/tex]
=> [tex]k = 14.33 \ N/m[/tex]
Generally the spring constant is also mathematically represented as
[tex]k = \frac{ F }{x }[/tex]
=> [tex]14.33 = \frac{ 1.2 }{x }[/tex]
=> [tex]x = 0.084 \ m[/tex]
A storm front moves in and Rachel and Pam notice the column of mercury in the barometer rises only to 736 mm. Assume the density of mercury is 13, 000 kg/m 3
(a) What is the change in air pressure?
(b) What if their barometer was filled with water instead of mercury, how high does the column rise? Density of water = 1000 kg/m
Answer:
a
[tex]\Delta P = 7558.6 \ Pa[/tex]
b
[tex]h_1 = 10 \ m[/tex]
Explanation:
From the question we are told that
The position of the column of mercury in the barometer is [tex]h = 736 \ mm = 0.76 \ m[/tex]\
The density of mercury is [tex]\rho = 13,000 \ kg / m^3[/tex]
Generally the pressure of the atmosphere at that column is mathematically represented as
[tex]P = \rho * g * h[/tex]
=> [tex]P =13 000 * 9.8 * 0.736[/tex]
=> [tex]P = 93766.4 \ Pa[/tex]
Generally the atmospheric pressure at sea level (Generally the pressure before the change in level of the mercury column) is [tex]P_a = 101325 \ Pa[/tex]
Generally the change in air pressure is mathematically represented as
[tex]\Delta P = P_a - P[/tex]
=> [tex]\Delta P = 101325 - 93766.4[/tex]
=> [tex]\Delta P = 7558.6 \ Pa[/tex]
Generally the height which the column will rise to is mathematically evaluated as
[tex]h_1 = \frac{P}{ \rho_w * g }[/tex]
Here [tex]\rho_w[/tex] is the density of water with value [tex]\rho_w = 1000 \ kg/m^3[/tex]
So
[tex]h_1 = \frac{ 93766.4}{ 1000 * 9.8 }[/tex]
=> [tex]h_1 = 10 \ m[/tex]