Answer:
The sound level of the point source at a distance of 10 meters is approximately 110.294 decibels.
Explanation:
First, we calculate the intensity ([tex]I[/tex]), in watts per square meter, by the Inverse-Square Law:
[tex]I= \frac{\dot W}{4\pi\cdot r^{2}}[/tex] (1)
Where:
[tex]\dot W[/tex] - Power, in watts.
[tex]r[/tex] - Radius, in meters.
And the sound intenity level ([tex]L[/tex]), in decibels, is expressed by:
[tex]L = 10\cdot \log_{10} \frac{I}{I_{o}}[/tex] (2)
Where [tex]I_{o}[/tex] is the reference sound intensity, in watts per square meter.
If we know that [tex]\dot W = 135\,W[/tex], [tex]r = 10\,m[/tex] and [tex]I_{o} = 10^{-12}\,\frac{W}{m^{2}}[/tex], then we find that sound level at a distance of 10 meters is:
[tex]I= \frac{\dot W}{4\pi\cdot r^{2}}[/tex]
[tex]I = 0.107\,\frac{W}{m^{2}}[/tex]
[tex]L = 10\cdot \log_{10} \frac{I}{I_{o}}[/tex]
[tex]L \approx 110.294\,dB[/tex]
The sound level of the point source at a distance of 10 meters is approximately 110.294 decibels.
please answer soon
a car is traveling along the highway at a constant velocity, what must be true about all the forces acting on the car?
How do officers in this line of work need to use problem solving and critical thinking to do their jobs?
Answer:
by using problem solving skills they could solve who,what,where did the crime oriented. and using critical thinking is good for you to get the job done!
Explanation:
I'm in forensic science :)
What is the relationship between temperature and kinetic energy?
Answer:
temperature is the average kinetic energy of the particles of matter. the hotter something is the more kinetic energy it has.
Explanation:
Which of the following scenarios would result in an increase of kinetic
energy?*
A) An object at rest at a height of 10 meters
B) A car accelerating from 10 m/s to 20 m/s
C) A car coming to a stop
Answer:
B) A car accelerating from 10 m/s to 20 m/s
Explanation:
I explained this yesterday.
How is our magnetic field made?
Answer:
REVENGE
Explanation:
HAHAAHAHAAHAHAHA
A 100 L ball is blown up inside at 200K. It is then taken outside in the hot sun, and the volume increases to 150 L. What is the new temperature?
Answer:
Temperature, T2 = 300 Kelvin
Explanation:
Given the following data;
Initial volume = 100 Liters
Initial temperature = 200 Kelvin
Final volume = 150 Liters
To find the final temperature T2, we would use Charles' law.
Charles states that when the pressure of an ideal gas is kept constant, the volume of the gas is directly proportional to the absolute temperature of the gas.
Mathematically, Charles is given by;
[tex] \frac {V}{T} = K[/tex]
[tex] \frac{V1}{T1} = \frac{V2}{T2}[/tex]
Making T2 as the subject formula, we have;
[tex] T_{2}= \frac{V_{2}}{V_{1}} * T_{1}[/tex]
Substituting into the formula, we have;
[tex] T_{2}= \frac{150}{100} * 200[/tex]
[tex] T_{2}= 1.5 * 200 [/tex]
Temperature, T2 = 300 Kelvin
A man is out roller skating and swerves to miss a crowd. If his curved path has a radius of 2.0 m and he experiences a centripetal force of 5.0 m/s2, what is his speed?
1.6 m/s
3.2 m/s
0.63 m/s
10. m/s
Answer:
0.63
Explanation:
because i used the sin symbol
why is fluorine more chemically reactive than
nitrogen?
Answer:
Nitrogen has Electronic configuration 1s2 2s2 2p3. Fluorine has Electronic configuration 1s2 2s2 2p5 i.e. nitrogen has half filled p subshell that makes it more stable than fluorine and fluorine requires only 1 electron to complete it's octet to get stable..Therefore Fluorine is more reactive than Nitrogen.
Hope it helps you
when do i know if the acceleration (a) in newtons second law is 0?
Answer:
When the sum of all forces applied to the object is 0.
Explanation:
N2L states that net force equals an object's mass times its acceleration (F = ma). If the net force is 0, the acceleration of the object is 0.
On the second note, when an object has 0 acceleration (which means it has a constant velocity), it is in equilibrium (N1L).
When acceleration and velocity are the in the same direction, the speed will
Answer:
slowing down.
Explanation:
acceleration points in the same direction as the velocity, the object will be speeding up. And if the acceleration points in the opposite direction of the velocity, the object will be slowing down
If a species experiences a helpful mutation, like camouflage, explain how that mutation would help the species to better I survive and flourish. Again, be sure to explain how and why that mutation would be helpful.
HELP I NEED IT FAST PLEASE ILL MARK B!!!! IF CORRECT
A lightbulb has 25 W stamped on it. What does this mean?
Answer:
A lightbulb has 25 W stamped on it. What does this mean?:
These labels mean that each lightbulb has Its respective power delivered to It when It Is connected to a constant
Explanation:
The screens show two sound waves that last the same amount of time. Which wave has a higher frequency? Explain your answer
Answer:
Wave 1
Explanation:
Its a High frequency waves the high waves are closer to each other thme the lower ones
Human perception of the frequency of sound waves is called:
Answer:
The study of the human perception of sound is called psychoacoustics.
Explanation:
Question 5 of 10
What are two things that happen when a home computer scanner uses
electromagnetic waves?
A. Red light shines on patterns of black and white, recording the
pattern of reflected light.
B. Objects are exposed to X-rays, which either pass through or are
absorbed by the objects.
C. A silicon chip releases electrons by the photoelectric effect,
producing an image.
D. A charge-coupled device captures visible light that is reflected off
an object
Answer: B. Objects are exposed to X-rays, which either pass through or are
absorbed by the objects.
C. A silicon chip releases electrons by the photoelectric effect,
producing an image.
Explanation:
Which of the following is NOT true about noon in the Northern Hemisphere, on January 1?
A. The sun has reached its highest altitude for that day.
B. Your shadow is the shortest it will be that day.
C. Your shadow points due north.
D. The Sun is directly overhead.
Answer:
The answer is D
Explanation:
The three main stages to the memory process are encoding, storage, and retrieval.
A.True B.False
Answer:
A
Explanation:
Answer:
a- true
Explanation:
i did the test and its correct
An elevator is rising up a vertical shaft in a skyscraper. Between the 12th and 20th floors, it travels at a constant speed. During this time period:
1.) The only unbalanced force acting on it is air resistance.
2.) The forces acting on it are balanced so the net force is zero.
3.) The upward force is greater than the combined downward forces of gravity and air resistance, making it move upward.
4.) There are no forces acting on it so the net force is zero.
PLSS HELPP
Are humans evolving? What will humans look like in 100,000 years in the future or longer?
Answer:
yes
Explanation:
How fast is a 0.50 kg ball moving if it's kinetic energy is 400 j
Answer:
Correct 40 m/s
Explanation:
the ratio between the force of sliding friction and the normal force of an object is called?
A. The rolling friction
B. The drag
C. The coefficient of friction
D. The starting friction
Answer:
the coefficient of friction
convert 172 to a scientific notation
Answer:
1.72×10^2
Explanation:
Is the answer correct ?
A student of mass 45kg, who is undergoing National Service training, takes 6s to climb a flight of stairs that had 36 steps. If each step is 16cm high, what is the power of the student?
Answer:
Approximately [tex]4.2 \times 10^{2}\; \rm W[/tex] on average in the vertical direction (assuming that [tex]g = 9.8\; \rm N \cdot kg^{-1}[/tex].)
Explanation:
Vertical displacement of this student in [tex]6\; \rm s[/tex]: [tex]36 \times 16\; \rm cm = 36 \times (0.16\; \rm m) = 5.76\; \rm m[/tex].
Average vertical velocity of this student: [tex]v = \displaystyle \frac{5.76\; \rm m}{6\; \rm s} = 0.96\; \rm m \cdot s^{-1}[/tex].
The average vertical force that this student exerts on the ground would be equal to the weight of this student:
[tex]F = W = m \cdot g = 45\; \rm kg \times 9.8\; \rm N \cdot kg^{-1} = 441\; \rm N[/tex].
The average power of this student in the vertical direction is equal to the product of the force and velocity of this student in that direction:
[tex]P = F \cdot v = 441\; \rm N \times 0.96\; \rm m \cdot s^{-1} \approx 4.2\times 10^{2}\; \rm W[/tex].
will give you brainliest pls help
1. All the relevant resistors are in series, so the total (or equivalent) resistance is the sum of the resistances of the resistors: 20 Ω + 80 Ω + 50 Ω = 150 Ω [choice A].
2. The ammeter will read the current flowing through this circuit. We can find the ammeter reading using Ohm's law in terms of the electromotive force provided by the battery: I = ℰ/R = (30 V)(150 Ω) = 0.20 A [choice C].
3. The voltmeter will measure the potential drop across the 50 Ω resistor, i.e., the voltage at that resistor. We know from question 2 that the current flowing through the resistor is 0.20 A. So, from Ohm's law, V = IR = (0.20 A)(50 Ω) = 10. V, which will be the voltmeter reading [choice F].
4. Trick question? If the circuit becomes open, then no current will flow. Moreover, even if the voltmeter were kept as element of the circuit, voltmeters generally have a very high resistance (an ideal voltmeter has infinite resistance), so the current moving through the circuit will be negligible if not nil. In any case, the ammeter reading would be 0 A [choice B].
A Navy vessel is traveling due north during wartime. A torpedo has been launched by an enemy directly toward the stern (rear) of the vessel. Can the vessel outrun the torpedo if both continue in a straight line due north?
A) Yes, the Navy vessel is faster
B) No, the Navy vessel is slower
C) Maybe, since both travel at the same speed
D) Maybe, based on the temperature of the water
Answer:
The correct option is;
B) No, the Navy vessel is slower
Explanation:
The speed of some torpedoes can be as high as 370 km/h. The average speed of a fast Navy vessel is approximately 110 km/h
Therefore, the torpedoes travel approximately 3 times as fast as the (slower) Navy vessel, such that the torpedo covers three times the distance of the Navy vessel in the same time and therefore, if the Navy vessel and the torpedo continue in a straight line (in the same direction) due north the vessel can not outrun the torpedo
Therefore, no the Navy vessel travels slower than a torpedo.
A ball with a volume of 1.0 L is filled with a gas at 5 atmospheres (atm). If the volume is reduced to 0.75 L without a change in temperature, what would be the pressure of the balloon?
Answer:
P2 = 6.67 atm
Explanation:
Given the following data;
Initial volume = 1 Liters
Initial pressure = 5 atm
Final volume = 0.75 Liters
To find the final pressure P2, we would use Boyles' law.
Boyles states that when the temperature of an ideal gas is kept constant, the pressure of the gas is inversely proportional to the volume occupied by the gas.
Mathematically, Boyles law is given by;
[tex] PV = K[/tex]
[tex] P_{1}V_{1} = P_{2}V_{2} [/tex]
Substituting into the equation, we have;
[tex] 5 * 1 = P_{2} * 0.75 [/tex]
[tex] 5 = 0.75_{2} [/tex]
[tex] P_{2} = \frac {5}{0.75}[/tex]
[tex] P_{2} = 6.67[/tex]
P2 = 6.67 atm
Therefore, the new pressure is 6.67 atm.
A 7 kg ball is push with a force of 28 N. What is the acceleration? .
Answer:
a = 4 m/s²
Explanation:
Given: 28 N, 7 kg
To find: Acceleration (a)
Solution: To find (a), divide force by weight
A = F ÷ m
= 28 ÷ 7
= 4 m/s²
Newtons are derived units, equal to 1 kg-m/s². In other words, a single Newton is equal to the force needed to accelerate one kilogram one meter per second squared.
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A 5 kg ball is sitting on top of a hill. It has a Potential Energy of 6000J. What is the height of the ball?
Answer:
h = 122.44 m
Explanation:
Given that,
Mass of a ball, m = 5 kg
Potential energy at the top of the hill, E = 6000 J
We need to find the height of the hill. The formula for the potential energy is given by :
[tex]P=mgh\\\\h=\dfrac{P}{mg}\\\\h=\dfrac{6000}{5\times 9.8}\\\\h=122.44\ m[/tex]
So, the height is 122.44 m.
Which equation could not be used to determine straight line acceration?
Answer:
the answer for the question is the last option
You observed the wheels of a car as it moves past you from right to left. Do the wheels have a positive or negative angular velocity?
Answer:
Negative angular velocity
Explanation:
The movement/rotation of An object in a clockwise direction ( right to left direction) corresponds to a Negative angular velocity . while the rotation of an object in an anti-clockwise direction ( left to right direction ) possess a positive angular velocity.
Hence the movement of the wheels of the car past you from right to left will possess a Negative angular velocity