Suppose that the separation between two speakers A and B is 6.60 m and the speakers are vibrating in-phase. They are playing identical 126-Hz tones and the speed of sound is 343 m/s. An observer is seated at a position directly facing speaker B in such a way that his line of sight extending to B is perpendicular to the imaginary line between A and B. What is the largest possible distance between speaker B and the observer, such that he observes destructive interference
Answers
Complete question
The diagram for this question is shown on the first uploaded image
Answer:
The largest possible distance is [tex]e = 15.33 \ m[/tex]
Explanation:
From the question we are told that
The separation between Speaker at position A and B is AB = 6.60 m
The frequency of the tune which the speaker are playing is [tex]f = 126 \ Hz[/tex]
The speed of sound is [tex]v = 343 \ m/s[/tex]
Generally the wavelength of the tune playing is mathematically represented as
[tex]\lambda = \frac{v}{f}[/tex]
=> [tex]\lambda = \frac{343}{ 126}[/tex]
=> [tex]\lambda = 2.72 \ m[/tex]
Let the observer be at position D
Generally the distance A and is mathematically evaluated using Pythagoras theorem as
[tex]AC = \sqrt{AB ^2 + BC^2}[/tex]
Let BC = e
So
[tex]AC = \sqrt{6.60 ^2 + e^2}[/tex]
Generally the path difference between the first and the second speaker from the observer point of view is mathematically represented as
[tex]P = AC - BC[/tex]
=> [tex]P = \sqrt{6.60 ^2 + e^2} - e[/tex]
Generally the condition for destructive interference is mathematically represented as
[tex]P = (2n - 1 )\frac{\lambda}{2}[/tex]
Here n is the order of the fringe which is one
=> [tex]\sqrt{6.60 ^2 + e^2} - e = (2 * 1 - 1 )\frac{2.72}{2}[/tex]
=> [tex]\sqrt{6.60 ^2 + e^2} - e = 1.36[/tex]
=> [tex]6.60 ^2 + e^2 =( 1.36 +e)^2[/tex]
=> [tex]6.60 ^2 + e^2 =1.8496 + 2.72e +e^2[/tex]
=> [tex]e = 15.33 \ m[/tex]
Related Questions
You have to move your 100 N couch before a delivery company drops off your new one. Unfortunately your roommate is passed out on it. The coefficient of friction between the couch and floor is .43. It takes 250 N of force to get the couch moving. a) How much does your roommate weigh in Newton’s? b) After you get the couch moving it only takes 200 N to keep it moving at a constant speed, what is the coefficient of kinetic friction?
Answers
Answer:
a) Weight of Roommate = 481.4 N
b) μk = 0.34
Explanation:
a)
The force required to move the couch must be equal to the force of friction:
F = frictional force
F = μW
W = F/μ
where,
W = Total Weight of Couch and Roommate
F = Force Required start to move couch = 250 N
μ = coefficient of static friction between couch and floor = 0.43
Therefore,
[tex]W = \frac{250 N}{0.43}\\\\W = 581.4 N[/tex]
So, the total weight is given as:
W = Weight of Couch + Weight of Roommate
Weight of Roommate = W - Weight of Couch
Weight of Roommate = 581.4 N - 100 N
Weight of Roommate = 481.4 N
b)
Now, the force required to keep the couch moving can be given as equal to the kinetic friction force:
F = kinetic friction
F = μk*W
μk = F/W
where,
μk = coefficient of kinetic friction = ?
F = Force required to keep the couch moving = 200 N
Therefore,
μk = 200 N/581.4 N
μk = 0.34
A 300 g bird flying along at 6.0 m/s sees a 10 g insect heading straight toward it with a speed of 30 m/s. the bird opens its mouth wide and enjoys a nice lunch. What is the bird's speed immediately after swallowing?
Answers
Answer:
6.77m/s
Explanation:
Using the law of conservation of momentum
m1u1 + m2u2 = (m1+m2)v
m1 and m2 are the masses of the object
u1 and u2 are the velocities before collision
v is the final collision
Given
m1 = 300g = 0.3kg
u1 = 6.0m/s
m2 = 10g = 0.01kg
u2 = 30m/s
Required
The bird's speed immediately after swallowing v
Substitute the given values into the formula
m1u1 + m2u2 = (m1+m2)v
0.3(6) + 0.01(30) = (0.3+0.01)v
1.8+0.3 = 0.31v
2.1 = 0.31v
v = 2.1/0.31
v = 6.77m/s
Hence the bird's speed immediately after swallowing is 6.77m/s
A little girl pushes a 5.0 kg toy baby stroller at constant speed 7.0 m across the floor. She pushes on the handle with a force of 40 N at an angle of 30o with the horizontal. All parts are 4 points each.
Answers
Complete Question
1 a A little girl pushes a 5.0 kg toy baby stroller at constant speed 7.0 m across the floor. She pushes on the handle with a force of 40 N at an angle of 30o with the horizontal. How much work is done by the girl on the wagon?
1b A farmhand pushes 20 ㎏ bale of hay 4m across the floor of the barn if she exerts a horizontal force of 60 N on the hay, how much work is done? (5 pts)
All parts are 4 points each
Answer:
1a
[tex]W = 242.5 \ J[/tex]
1b
[tex]W = 240 \ J[/tex]
Explanation:
Considering question a
From the question we are told that
The mass of the toy baby stroller is [tex]m = 5.0 \ kg[/tex]
The distance covered is [tex]d = 7.0\ m[/tex]
The force the girl applies on the handle is [tex]F = 40 \ N[/tex]
The angle at which this force is applied is [tex]\theta = 30^o[/tex]
Generally the workdone is mathematically represented as
[tex]W = F_x * d[/tex]
Here [tex]F_x[/tex] is the force along the horizontal axis , this is mathematically represented as
[tex]F_x = F cos (\theta )[/tex]
=> [tex]F_x = 40 * cos(30 )[/tex]
=> [tex]F_x = 34.64 \ N[/tex]
So
[tex]W = 34.64 * 7[/tex]
=> [tex]W = 242.5 \ J[/tex]
Considering question b
From the question we are told that
The mass of the toy baby stroller is [tex]m = 20 \ kg[/tex]
The distance covered is [tex]d = 4 \ m[/tex]
The force the girl applies on the handle is [tex]F = 60 \ N[/tex]
Generally the workdone is mathematically represented as
[tex]W = F * d[/tex]
=> [tex]W = 60 * 4[/tex]
=> [tex]W = 240 \ J[/tex]
A ball of mass 4kg moving with a velocity of 20m/s collides with another ball of mass 15kg moving with a velocity of 15m/s in the same direction. Calculate the velocity of the 5kg ball if the collision is perfectly inelastic.
Answers
Answer:
velocity = 16.05 m/s
Explanation:
inelastic collision formula:
m1u1 + m2u2 = (m1 + m2)v
m1 = 4kg
u1 = 20m/s
m2 = 15kg
u2 = 15m/s
find v ?
m1u1 + m2u2 = (m1 + m2)v
(4×20) + (15×15) = (4+15)v
80 + 225 = 19v
305 = 19v
19v = 305
v = 305/19
v = 16.05 m/s
2. Using Graph 2, calculate the net force experienced by the particle between 4 and 6 seconds. The
particle has a mass of 0.25 kg.
A +5.0 N
B. +0.5 N
C. -0.5 N
D. -2.0 N
Answers
Using Newtons Second Law:
F = m×a
F = (0.25 kg)(-2 m/s²)
F = -0.5 N
The correct option is CAn object whose specific gravity is 0.850 is placed in water. What fraction of the object is below the surface of the water?
Answers
Answer:
The fraction of the object that is below the surface of the water is ¹⁷/₂₀
Explanation:
Given;
specific gravity of the object, γ = 0.850
Specific gravity is given as;
[tex]specific \ gravity = \frac{density \ of the \ object}{density \ of \ water}\\\\0.85= \frac{density \ of the \ object}{1000 \ kg/m^3} \\\\density \ of the \ object = 850 \ kg/m^3[/tex]
Fraction of the object's weight below the surface of water is calculated as;
[tex]= \frac{850}{1000} \ \times\ 100\%\\\\= 85 \% \\\\= \frac{17}{20}[/tex]
Therefore, the fraction of the object that is below the surface of the water is ¹⁷/₂₀
How fast, in meters per second, does an observer need to approach a stationary sound source in order to observe a 7.1 % increase in the emitted frequency?
Answers
Answer:
v0 = 24.42 m/s (Approx)
Explanation:
Given:
Increase in frequency = 7.1% =
Computation:
Assume n = 100%
n1 = [(v+v0)/(v+v1)]n
[100 + 7.1] = [(344+v0)/(344+0)]100
107.1 = [(344+v0)/(344)]100
v0 = 24.42 m/s (Approx)
what type of friction present when you wrench on a car?
Answers
Answer:Rolling friction is friction that acts on objects when they are rolling over a surface. Rolling friction is much weaker than sliding friction or static friction. This explains why most forms of ground transportation use wheels, including bicycles, cars, 4-wheelers, roller skates, scooters, and skateboards.
Explanation:
mester Exam 1 11 of 35
A car has an oil drip. As the car moves, it drips oil at a regular rate, leaving a trail of spots on the road. Which diagram shows the spots
of car that is continuously slowing down?
Answers
Define a rotation of the earth answer fast
Answers
Answer:
here u go
Explanation:
Earth's rotation is the rotation of planet Earth around its own axis. Earth rotates eastward, in prograde motion. As viewed from the north pole star Polaris, Earth turns counterclockwise.
if an atom was a scale, in which the nucleus is the size of an apple the electron.....
Answers
Answer:
the nucleus is the size of an apple, approximately 5 cm of radius e, the atom has a radius of R = 5 cm 104 = 50000 cm = 50 km
Explanation:
In the Rutherford experiments it was proved that the atomic nucleus has the volume 10-4 the volume of the atom.
If we make a scale design in which the nucleus is the size of an apple, approximately 5 cm of radius e, the atom has a radius of R = 5 cm 104 = 50000 cm = 50 km
This shows that almost the entire volume of the atom is empty.
What kind of electricity does turning wheel generates? Please help!
Answers
Answer: Kinetic Energy to Electrical.
Explanation: The magnet is rotated as a result of the spinning wheels, and this results in a powerful stream of electrons, therefore converting kinetic to electrical.
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.
Answers
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:
Use the image below to answer the question.
What does the arrow 'B' represent?
Question 7 options:
wavelength
refraction
frequency
compression
Answers
the maximum intensity levels of a trumpet, trombone, and a bass drum, each at a distance of 3m are 94 dB, 107dB, and 113dB respectively. What is the intensity level of the three different instruments when played simultaneously, again at 3m?
Answers
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
1. If a 4000 kg rocket reaches 7,000 m/s in 8 minutes after blastoff, what is its acceleration?
2. What force is being applied to the rocket?
3. What is the rocket's potential energy when it is 12 km off the ground?
(Hint - Change kilometers to meters)
4. If the rocket were to fall from the 12 km height, what would be its speed right before hitting the ground? (assume no air resistance)
+ answer all the questions plz
Answers
Answer:
I guess the Ans for second one is gravitational force
HELP ASAP!! i’ll mark you the brainliest!!
Answers
Answer:
yes
Explanation:
Calculate the change in entropy of 0.020 kg of ice when it melts at 0.0°C. The heat of fusion of ice is 3.36 x 10'J/kg.
Answers
Answer:
S = 2461.53 [kJ]
Explanation:
The change in entropy in a process such as melting can be calculated by means of the following expression.
[tex]S=\frac{H*m}{T}[/tex]
where:
S = entropy [kJ]
H = fusion heat = 3.36*10¹ [J/kg]
m = mass = 0.02 [kg]
T = temperature in kelvin = 273 [K]
[tex]S = \frac{0.02*3.36*10^{1} }{(273+0)}\\S = 2461.53 [kJ][/tex]
A stunt person jumps from the roof of a tall building, but no injury occurs because the person lands on a large, air-filled bag. Which one of the following best describes why no injury occurs?
A. The bag increases the amount of time during which the momentum is changing and reduces the average force on the person.
B. The bag increases the amount of time the force acts on the person and reduces the change in momentum.
C. The bag reduces the impulse to the person.
D. The bag provides the necessary force to stop the person.
E. The bag decreases the amount of time during which the momentum is changing and reduces the average force on the person.
Answers
Answer:
A stunt person jumps from the roof of a tall building, but no injury occurs because the person lands on a large, air-filled bag. Which one of the following best describes why no injury occurs?
The bag increases the amount of time during which the momentum is changing and reduces the average force on the person.
ANSWER: A
Answer:
A. The bag increases the amount of time during which the momentum is changing and reduces the average force on the person.
During stunts, people usually put an-air filled bag on the ground for safe landing and to prevent injuries.
Momentum is calculated by m* v where m is for mass and v is for velocity.
Force is directly proportional to momentum
F∝M
The bag in this scenario helps to increases the amount of time the force acts on the person. This implication means that there is a reduction in the change of momentum. Since Force and momentum have a directly proportional relationship then the Force taken to hit the floor is greatly reduced.
Read more on https://brainly.com/question/20362316
12 seconds after starting from rest a frewly falling cantaloupe has a speed of
Answers
Answer:
The cantaloupe has a speed of 117.6 m/s
Explanation:
Free Fall Motion
It occurs when an object falls under the sole influence of gravity. Any object that is being acted upon solely by the force of gravity is said to be in a state of free fall. Free-falling objects do not face air resistance.
If an object is dropped from rest in a free-falling motion, it falls with a constant acceleration called the acceleration of gravity, which value is [tex]g = 9.8 m/s^2[/tex].
The final velocity of a free-falling object after a time t is given by:
vf=g.t
The cantaloupe has been dropped from rest. We are required to find the speed after t=12 seconds.
Calculate the final speed:
vf=9.8 * 12 = 117.6 m/s
The cantaloupe has a speed of 117.6 m/s
what is the difference between alcoholic and Mercury thermometer based on their function?
Answers
While mercury freezes at -38 deg C
Mercury is/was better for human and other animal temps. High thermal coefficient of expansion mercury vs. alcohol = better resolution for small temperature changes in a medical application.
For higher temperatures alcohol will boil before mercury will.
What is the volume of a brick that is 30 cm long, 8 cm wide, and 10 cm tall?
Answers
I NEED BY JAN 4!!!!!!
Research what is known about Earth’s magnetic field. Begin by looking for images and credible sites on the Internet or refer to some books in a library. Answer the following questions:
What is the approximate size of Earth’s magnetic field?
Where are Earth’s magnetic poles?
Where is the magnet that causes Earth’s magnetic field located? What is this magnet made of?
Does Earth’s magnetic field move?
Answers
The earth has a magnetic field. It is much like a bar magnet. Imagine a gigantic bar magnet inside the Earth. But there is no giant magnet inside it.
To have a pretty good idea what earth's magnetic field is shaped like we imagine a bar magnet inside the earth.
The magnetic field is made by the motion of molten iron in earth's outer core. The swirling motion of molten iron changes all the time. Therefore, the magnetic fields will also get change. Then, the magnet poles also move.
The North pole and the south pole are two geographic poles of earth. These poles are the places on the earth's surface that earth's imaginary spin axis passes through.
There are two magnetic poles of the earth: North magnetic pole and South magnetic pole.
Earth's magnetic field is tilted a little bit. If we imagine that earth's magnetic field is made by a giant bar magnet. Then, the bar magnet would make an with earth's spin axis.
The geographic poles and the magnetic poles are not in the same place.
If we are standing at one magnetic poles then the magnetic field lines would be straight up and down.
Earth's magnetic field is a complex and dynamic phenomenon that is generated by the motion of molten iron in its outer core. The magnetic field extends far beyond the planet and is responsible for protecting Earth from harmful solar radiation and cosmic rays.
What is the approximate size of Earth's magnetic field?Earth's magnetic field is roughly dipolar in shape, meaning it has two main magnetic poles - north and south - and the field lines emerge from the north and re-enter at the south pole. The magnetic field has a strength of about 25-65 microteslas (μT) at the Earth's surface, and it extends for several tens of thousands of kilometers into space.
2. Where are Earth's magnetic poles?
Earth's magnetic poles are not fixed and are constantly moving due to the complex and dynamic nature of the planet's magnetic field. Currently, the north magnetic pole is located in the Arctic Ocean, close to Canada's Ellesmere Island, and the south magnetic pole is located in the Antarctic Ocean, near the coast of Antarctica.
3. Where is the magnet that causes Earth's magnetic field located? What is this magnet made of?
The magnet that causes Earth's magnetic field is not a physical magnet but rather a result of the motion of molten iron in the Earth's outer core. The outer core is a layer of liquid iron and nickel that surrounds the solid inner core. The motion of this molten iron generates electrical currents, which in turn create a magnetic field.
4. Does Earth's magnetic field move?
Yes, Earth's magnetic field is not static and is constantly changing due to the complex nature of the planet's interior. The magnetic poles are constantly moving and the strength of the magnetic field can vary over time. The magnetic field can also be influenced by external factors such as solar storms and changes in the solar wind. Scientists continue to study Earth's magnetic field to better understand its behavior and how it affects the planet.
Therefore, The magnetic field of the Earth is a complex and dynamic phenomenon caused by the movement of molten iron in its outer core. The magnetic field extends far beyond the planet and is in charge of shielding the planet from harmful solar radiation and cosmic rays.
To learn about cosmic rays click:
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One of the two rectangular components of a force is 20N and it makes an angle of 30
with the force. Find the magnitude of the other components.
Answers
Answer:
11.545NExplanation:
The the horizontal and vertical component be expressed as;
Fx = Fxos theta (horizontal compt)
Given Fx = 20N
theta = 30°
Get F:
20 = Fcos30
20 = 0.8660F
F = 20/0.8660
F = 23.09N
Get the magnitude of the other components. (vertical compt)
Fy = Fsin theta
Fy = 23.09sin30
Fy = 23.09(0.5)
Fy = 11.545N
Hence the magnitude of the other component is 11.545N
A street bridge is 5.5m long if the linear expansion of steel is 0.00001 oc How much will it expand when temperatures is by 10oc? Give answer in Cm
Answers
Answer:
[tex]l_o=550.055\ cm[/tex]
Explanation:
Given that,
Length of a street bridge, l = 5.5 m
The coefficient of bridge, [tex]\alpha =0.00001 ^0 C[/tex]
We need to find how much will it expand when temperatures is by 10°C.
The change in length per unit original length is given by :
[tex]\dfrac{\Delta l}{l}=\alpha \Delta T\\\\\Delta l = l\alpha \Delta T\\\\=5.5\times 0.00001 \times 10\\\\\Delta l=0.00055\\\\(l_o-l)=0.00055\\\\l_o=0.00055+5.5\\\\=5.50055\ m\\\\l_o=550.055\ cm[/tex]
Hence, the length will expanded 550.055 cm.
g While hauling a log in the back of a flatbed truck, a driver is pulled over by the state police. Although the log cannot roll sideways, the police claim that the log could have slid out the back of the truck when accelerating from rest. The driver claims that the truck could not possibly accelerate at the level needed to achieve such an effect. Regardless, the police write a ticket, and the drive
Answers
Answer:
The minimum coefficient of static friction required, µ = 0.10
Note. The question is incomplete. The complete question is given below:
While hauling a log in the back of a flatbed truck, a driver is pulled over by the state police. Although the log cannot roll sideways, the police claim that the log could have slid out the back of the truck when accelerating from rest. The driver claims that the truck could not possibly accelerate at the level needed to achieve such an effect. Regardless, the police write a ticket anyway and now the driver court date is approaching.
The log has a mass of m = 929 kg; the truck has a mass of M = 8850 kg. According to the truck manufacturer, the truck can accelerate from 0 to 55 mph in 23.0 seconds, but this does not account for the additional mass of the log. Calculate the minimum coefficient of static friction μs needed to keep the log in the back of the truck.
Explanation:
First, velocity in mph is converted to m/s
1 mph = 0.447 m/s
55 mph ≈ 24.6 m/s
The acceleration of the empty truck is a = v/t = 24.6 / 23 = 1.07 m/s²
Force that can be generated by the truck, F = ma
F = 8850kg * 1.07 m/s² = 9469.5 N
However, with the added mass of the log on it, the acceleration of the truck will become;
a = F / m = 9469.5 N / (8550+929)kg = 0.97 m/s²
Frictional force between the log and the truck = 0.97 m/s² * 929 kg = 901.13 N
Normal reaction on the truck due to the weight of the log, R = mg
R = 929 kg * 9.8m/s² = 9104.2 N
Coefficient of static friction, µ = F/R
µ = 901.13/9104.2
µ = 0.098 ≈ 0.10
Therefore, the minimum static friction required is µ = 0.10
What is food called when it enters the pharynx?
A.Bile
B.bolus
C. Food
D. Feces
Answers
Answer:
its food this was easy
This 200-kg horse ran the track at a speed of 5 m/s. What was the average kinetic energy?
Answers
Answer:
2500 JExplanation:
The average kinetic energy can be found by using the formula
[tex]k = \frac{1}{2} m {v}^{2} \\ [/tex]
m is the mass
v is the velocity
From the question we have
[tex]k = \frac{1}{2} \times 200 \times {5}^{2} \\ = 100 \times 25[/tex]
We have the final answer is
2500 JHope this helps you
Use the following free body diagram to answer questions 8 and 9:
8. Calculate the net force acting on the cart.
A 0N
B. +60N
C -60N
D. +240 N
9. Calculate the cart's rate of acceleration
A +60 m/s
B. +8 m/s
C.-2m/s
D. +2 m/s
Answers
Answer:
8 is c and 9 is b it is shown though the practice as god lol
Question 8
The net force acting on the cart is:
F = 150 N - 90 N
F = 60 N
Question 9
By the Newtons second law:
F = ma
Solving for a:
a = F/m
a = 60 N / 30 kg
a = 2 m/s²
Explain how polarization of a cell increases the cell's internal resistance.
(2
2.
Answers
Answer:
Explanation: The chemical action that occurs in the cell while the current is flowing causes hydrogen bubbles to form on the surface of the anode. This action is called POLARIZATION. Some hydrogen bubbles rise to the surface of the electrolyte and escape into the air, some remain on the surface of the anode. If enough bubbles remain around the anode, the bubbles form a barrier that increases internal resistance. When the internal resistance of the cell increases, the output current is decreased and the voltage of the cell also decreases.
A cell that is heavily polarized has no useful output. There are several methods to prevent polarization or to depolarize the cell.
One method uses a vent on the cell to permit the hydrogen to escape into the air. A disadvantage of this method is that hydrogen is not available to reform into the electrolyte during recharging. This problem is solved by adding water to the electrolyte, such as in an automobile battery. A second method is to use material that is rich in oxygen, such as manganese dioxide, which supplies free oxygen to combine with the hydrogen and form water.
A third method is to use a material that will absorb the hydrogen, such as calcium. The calcium releases hydrogen during the charging process. All three methods remove enough hydrogen so that the cell is practically free from polarization.
LOCAL ACTION
When the external circuit is removed, the current ceases to flow, and, theoretically, all chemical action within the cell stops. However, commercial zinc contains many impurities, such as iron, carbon, lead, and arsenic. These impurities form many small electrical cells within the zinc electrode in which current flows between the zinc and its impurities. Thus, the chemical action continues even though the cell itself is not connected to a load.
Local action may be prevented by using pure zinc (which is not practical), by coating the zinc with mercury, or by adding a small percentage of mercury to the zinc during the manufacturing process. The treatment of the zinc with mercury is called amalgamating (mixing) the zinc. Since mercury is many times heavier than an equal volume of water, small particles of impurities weighing less than mercury will float to the surface of the mercury. The removal of these impurities from the zinc prevents local action. The mercury is not readily acted upon by the acid. When the cell is delivering current to a load, the mercury continues to act on the impurities in the zinc. This causes the impurities to leave the surface of the zinc electrode and float to the surface of the mercury. This process greatly increases the storage life of the cell.