Answer:
A. Trial and error
Explanation:
Trial and error method is a method adopted when trying to solve a quadratic equation. This equation is mostly the balancing of the right hand side and the left hand side in-order to form a unique point or to equate to zero when one is subtracted from the other. In trail and error method, the coefficients is used to determine when the actual equation is balanced and the likely answer it should be if the equation is expanded through multiplication method.
Make a claim about which fossil in the diagram is the oldest. Use evidence and scientific reasoning to support your claim.
From the diagram, the fossil of fish is considered the oldest fossil. Because the oldest fossils are formed at the bottom whereas the others are at the top of the soil.
What are the fossils?When living organisms like plants, animals, and human beings are died, their bodies get buried in the form of sediments in the sand, rock water bodies, etc..,
It also includes the preserved remains of life for more than 10,000 years. It is the preserved remains, sediments, and impressions to trace the life of the organisms and their behavior.
When living organisms died and are buried in sand or mud, the tissues of living organisms get decomposed leaving the bones which is harder. After the organisms are buried in the sand or mud, several sediments, and sand was built over the top of the buried organisms.
These sand and sediments over the buried organisms eventually form the layer of rocks. This is how fossils are made and these fossils were identified when the rocks were broken or by cause of soil erosion.
The age of the fossils was identified by the stacks of layered rocks with the help of the superposition principle. The oldest fossils are present at the bottom of the rocks whereas the youngest fossils are present at the top of the rocks. This process is called Relative dating.
Hence, from the given diagram the fossil of fish is present at the bottom of the rock unlike the others fossils like monkeys and lizard. Thus, the oldest fossil is fish and the youngest one is a monkey.
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Definition of continental polar
cold, dry, and stable air masses .
In a laser cutting process of aluminum plates of 1mm thick, a through hole is to be drilled, followed by melting-dominated cutting. If the focused laser beam is 0.25 mm in diameter (assuming it is the same of the cut width w), (a) In order to drill a hole through the plate in 1 ms, determine the laser power required. (b) In the cutting, the laser power is adjusted to be 1,500W. Determine the cutting velocity V achievable.
Answer:
a) P = 118.4 W, b) t = 7.9 10⁻⁵ s
Explanation:
a) Let's analyze this interesting exercise a bit, we suppose that all the laser
energy is used to heat the aluminum, we should calculate the energy necessary to bring the solid aluminum to the melting temperature and add the energy to carry out the change of solid state to liquid,
let's use the calorimeter equation
Q₁ = m c_e ΔT
and the energy of change of these solid to liquid (fusion process)
Q₂ = m L
the energy required to create the hole is
Q_ {total} = Q₁ + Q₂
if there are no losses this is the laser energy
E = Q_ {total}
The aluminun data c_e =9000 J/kgC, L = 322 103 J/kg, ρ = 2.7 103 kg/m3 , T₂ = 660C, T₀= 25C
Let's find the mass of the hole, which we approximate by a cylinder of diameter d = 0.25 mm = 0.25 10⁻³ m and a thickness of e = 1 mm = 1 10⁻³ m
let's use the concept of density
ρ = m / V
the volume of a cylinder is
V = π r² e = π (d²/4) e
we substitute
m = [tex]\rho \pi \frac{d^2 e}{4}[/tex]
let's calculate
m = π/4 2.7 10³ (0.25 10⁻³)² 1 10⁻³
m = 1,325 10⁻⁷ kg
we calculate the energy
E = 1,325 10⁻⁷ 900 (660 - 25) + 1,325 10⁻⁷ 322 10³
E = 7.57 10⁻² + 4.27 10⁻²
E = 1.184 10⁻¹ J
Let's use the power ratio
P = E / t
P = 0.1184 /1 10⁻³
P = 118.4 W
b) In this part they indicate that the laser power is P = 1500 W, find the time to deposit the energy to melt the aluminum
P = E / t
t = E / P
t = 0.1184 / 1500
t = 7.9 10⁻⁵ s
There is only one temperature where the Celsius and Fahrenheit thermometers will read the same and no conversions need to be made. What is it?
A. -25 degrees
B. -40 degrees
C. 25 degrees
D. 0 degrees
Answer:
-40 degrees
Explanation:
I just took the Temperature Quiz and got it right. :)
g n diffraction, the formula for minima is given by a times s i n (theta )equals m lambda, where a is the width of the slit, theta is the angle of dispersion, m is the order, and lambda is the wavelength. For a wavelength of 630 nm, m equals 3, and a equals 5 times 10 to the power of negative 6 end exponent m. Calculate the angular spread in Degrees. Enter only the numerical value (i.e. omit the unit abbreviations when inputting your answer into Blackboard).
Answer:
θ = 22.2
Explanation:
This is a diffraction exercise
a sin θ = m λ
The extension of the third zero is requested (m = 3)
They indicate the wavelength λ = 630 nm = 630 10⁻⁹ m and the width of the slit a = 5 10⁻⁶ m
sin θ = m λ / a
sin θ = 3 630 10⁻⁹ / 5 10⁻⁶
sin θ = 3.78 10⁻¹ = 0.378
θ = sin⁻¹ 0.378
to better see the result let's find the angle in radians
θ = 0.3876 rad
let's reduce to degrees
θ = 0.3876 rad (180º /π rad)
θ = 22.2º
a particle moves along of the x_axis according to the equation X=2t+3t^2, whare x is in m and t is in second. calcualt the instantaneous velocity and the instantaneous acceleration in t=3s
Answer:
Instantaneous velocity [tex]= 20[/tex] meter per second
Instantaneous acceleration [tex]= 6[/tex] meter per second square
Explanation:
Given equation of distance X = [tex]2t+3t^2[/tex]
Instantaneous velocity [tex]= \frac{dX}{dt}[/tex] [tex]= 2 + 6 t[/tex]
Substituting the value of t = 3 seconds, we get -
[tex]\frac{dX}{dt} = 2 + 6*3 = 20[/tex] meter per second
Instantaneous acceleration [tex]= \frac{d^2X}{dt^2}[/tex] [tex]= 6[/tex] meter per second square
Two resistors 5 ohm's each can be combined to give an equivalent resistance of
Answer: 10 Ω or 2.5 Ω
Explanation:
In series resistance R = 5 Ω + 5 Ω =10 Ω. If resistors are parallel, resistance is
1/R = 1/5Ω+ 1/5Ω and R = 2,5 Ω
what is the minimum effort required to raise the block?
Answer:
2000 N.
Explanation:
From the question given above, the following data were obtained:
Load (L) = 8000 N
Mechanical advantage (MA) = 4
Effort (E) =?
The mechanical advantage of a machine is simply defined as:
Mechanical advantage = Load / Effort
MA = L / E
With the above formula, we can obtain the effort used to raise the load of 8000 N as follow:
Load (L) = 8000 N
Mechanical advantage (MA) = 4
Effort (E) =?
MA = L / E
4 = 8000 / E
Cross multiply
4 × E = 8000
Divide both side by 4
E = 8000 / 4
E = 2000 N
Thus, the effort used to raised the load is 2000 N.
Low air pressure and warm temperatures over land are most likely to result in which of the following weather conditions or events?
A.Clear sunny skies
B. tropical hurricane
C. chance of snow
D.Cloudy skies with rain
a violin is less than 0.5 m long. a bass fiddle is more than 1.5 m long. which instrument do you expect to be able to play notes with a lower pitch and why?
Explanation:
When there is a high frequency sound the speed of the vibrations is faster and makes a high pitch sound. When there is a low frequency sound the speed of the vibrations is slower and makes a lower pitch sound.
What number belongs where "X" is to properly balance this equation?
2 NaCl →
2 Na + Ecl2
04
o
2.
оо
Answer:
Option D: 1
Explanation:
The chemical equation given is;
2NaCl = 2Na + XCl2
We want to find the value of X.
On the left hand side, we can see we have 2 moles of both Na and Cl.
On the right hand side, we can see that we have 2 moles of Na and also 2 moles of Cl. Thus, the equation is balanced and as such X = 1
What determines the precision of a measurement?
Answer:
Precision is determined by a statistical method called a standard deviation To determine if a value is precise find the average of your data, then subtract each measurement from it
What is R2 in the circuit?
WILL GIVE BRAINLIEST !!!!
Answer:
1. Rₑq = 4 Ω
2. R₂ = 6 Ω
3. Vₜ = 12 V, V₁ = 12 V, V₂ = 12 V
4. Iₜ = 3 A, I₁ = 1 A, I₂ = 2 A
Explanation:
1. Determination of the equivalent resistance
Voltage (V) = 12 V
Current (I) = 3 A
Resistance (Rₑq) =?
V= IRₑq
12 = 3 × Rₑq
Divide both side by 3
Rₑq = 12 / 3
Rₑq = 4 Ω
Thus, the equivalent resistance (Rₑq) = 4 Ω
2. Determination of R₂.
Equivalent resistance (Rₑq) = 4 Ω
Resistance 1 (R₁) = 12 Ω
Resistance 2 (R₂)
Since the resistor are in parallel arrangement, the value of R₂ can be obtained as follow:
Rₑq = R₁ × R₂ / R₁ + R₂
4 = 12 × R₂ / 12 + R₂
Cross multiply
4(12 + R₂) = 12R₂
48 + 4R₂ = 12R₂
Collect like terms
48 = 12R₂ – 4R₂
48 = 8R₂
Divide both side by 8
R₂ = 48 / 8
R₂ = 6 Ω
3. Determination of the total voltage (Vₜ), V₁ and V₂.
From the question given above, the total voltage is 12 V
Since the resistors are arranged in parallel connection, the same voltage will go through them.
Thus,
Vₜ = V₁ = V₂ = 12 V
4. Determination of the total current (Iₜ), I₁ and I₂
From the question given above, the total current (Iₜ) is 3 A
Next, we shall determine I₁. Since the resistors are arranged in parallel connection, different current will pass through each resistor respective.
Vₜ = V₁ = 12 V
R₁ = 12 Ω
I₁ =?
V₁ = I₁R₁
12 = I₁ ×12
Divide both side by 12
I₁ = 12 / 12
I₁ = 1 A
Next, we shall determine I₂. This can be obtained as follow:
Iₜ = 3 A
I₁ = 1 A
I₂ =?
Iₜ = I₁ + I₂
3 = 1 + I₂
Collect like terms
I₂ = 3 – 1
I₂ = 2 A
a pool and stops at the
Which best describes his
motion?
A. Linear
B. Projectile
C. Vibrational
In Linear motion the swimmer swims
Answer: A
Explanation: Linear motion.
a car is travelling at 18m/s accelerates ti 30m/s in 3seconds. what's the acceleration of the car
[tex] \Large {\underline { \sf {Required \; Solution :}}}[/tex]
We have ―
Initial velocity, u = 18 m/sFinal velocity, v = 30 m/sTime taken, t = 3 secondsWe've been asked to calculate acceleration.
[tex]\qquad \implies\boxed{\red{\sf{ a = \dfrac{v-u}{t} }}}\\[/tex]
a denotes accelerationv denotes final velocityu denotes initial velocityt denotes time[tex] \twoheadrightarrow \quad \sf {a = \dfrac{30-18}{3} \; ms^{-2} } \\ [/tex]
[tex] \twoheadrightarrow \quad \sf {a =\cancel{ \dfrac{12}{3} \; ms^{-2} }} \\ [/tex]
[tex]\twoheadrightarrow \quad \boxed{\red{\sf{ a = 4 \; ms^{-2} }}}\\[/tex]
Therefore, acceleration of the car is 4 m/s².
A student is provided with a rubber cylinder and a patch of synthetic fur. The rubber cylinder and the patch are electrically neutral. The student rubs the cylinder back and forth along the fur. A short time later, after the cylinder and fur have been placed on insulating stands, the student determines that the fur has a net negative electric charge. Before the patch of fur attained its net negative charge, it was considered to be electrically neutral. Which of the following claims, with appropriate evidence, is correct about the distribution of charge in the patch of fur before the charging process?
a. It is an isolated system.
b. It is a closed system.
c. It is an open system.
d. The type of system cannot be determined unless information is known about the net force exerted on the system at any given time.
Answer:
Option b ( It is a closed system) is the appropriate answer.
Explanation:
The mass transfer isn't made on a platform. There seems to be no mass transfer, the mechanism can't be separated as power lines will interfere beyond the physical boundaries including its fur patch.The mechanism can't however be separated and, while the mass transfer is indeed not present, several field lines will communicate well outside the mechanism.The other options are not linked to the situation in question. Thus, the answer is correct.
!Please help fast!!*18 pts*!
How is light amplified in a laser?
A. Photons "leak" through a partically reflecting mirror, causing them to travel in step.
B. Integrated circuits in a laser amplify the sound produced by photon emission.
C. Photons collide with gas particles, multiply, and reflect back and forth in a tube.
D. Electric current is amplified and directed into gas particles, which emit photons.
Answer:
A.
Explanation:
Some of these photons are absorbed by the atoms in the ground state and the photons are lost to the laser process. However, some photons cause stimulated emission in excited-state atoms, releasing another coherent photon. In effect, this results in optical amplification
A block of wood and a block of aluminum have been sitting out for a while. How do their temperatures compare?
Answer:
Block of aluminum
Explanation:
The block of aluminum because of the conductivity, and is a metal, so it gets hotter faster
The temperature of wood and the aluminium will depend upon thier thermal coductivity.
What is thermsal conductivity?The thermal conductivity of any material is defined as the amount of heat from a material can flow in a unit area per unit degree centigrade for a unit distance.
The thermal conductivity of wood is around 0.90 to 0.197 w/mk and that of aluminium is around 88 to 251 w/mk.
We can see that the aluminium block will absorb much amount of heat as compared to the wood block. Because the thermal conductivity of aluminium is much higher then the wood.
Hence temperature of wood and the aluminium will depend upon thier thermal coductivity.
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A piano tuner stretches a steel piano wire with a tension of 765 N. The steel wire has a length of 0.800 m and a mass of 6.00 g . What is the frequency f1 of the string's fundamental mode of vibration
Answer:
the frequency of the fundamental mode of vibration is 199.6 Hz
Explanation:
Given;
tension of the piano wire, T = 765 N
length of the steel wire, L = 0.8 m
mass of the steel wire, m = 6.00 g = 6 x 10⁻³ kg
The frequency of the fundamental mode of vibration is calculated as;
[tex]f_o = \frac{1}{2l} \sqrt{\frac{T}{\mu} }[/tex]
where;
μ is the mass per unit length [tex]= \frac{6.0 \times 10^{-3}}{0.8} = 7.5 \times 10^{-3} \ kg/m[/tex]
[tex]f_o = \frac{1}{2l} \sqrt{\frac{T}{\mu} } \\\\f_o = \frac{1}{2\times 0.8} \sqrt{\frac{765}{7.5 \times 10^{-3}} } \\\\f_o = 199.6 \ Hz[/tex]
Therefore, the frequency of the fundamental mode of vibration is 199.6 Hz
Find the velocity of an object that has a mass of 500x10-6 kg and a charge of 1pc if it starts from
rest and passes through a potential difference of 120kV
Answer:
v = 4.8 10⁻⁴ m / s
Explanation:
To solve this exercise we can use the concepts of energy. In this case the potential energy is transformed into kinetic energy
U = K
q V = ½ m v²
v = [tex]\sqrt { \frac{2qV}{m} }[/tex]
in the exercise they indicate the value of the charge q₁ = 1 pC = 1 10⁻¹² C
let's calculate
v = [tex]\sqrt{ \frac{2 \ 1 \ 10^{-12} 120 \ 10^3}{500 ^{2} }[/tex]
v = 4.8 10⁻⁴ m / s
customer complains of an aluminum foil mixed with his salad? what will you do?
Answer:
offer them a refund or a remake/ replacement of food item whilst apologizing sincerely
Which of the following is a true statement for a child's toy spinning in a circle at constant speed?
a) The speed is constant, the velocity is constant, and the angular velocity is constant. b) The speed is constant, the velocity is not constant, and the angular velocity is constant. c) The speed is constant, the velocity is not constant, and the angular velocity is not constant. d) The speed is constant, the velocity is constant, and the angular velocity is not constant.
explain your answer.
Answer:
B
Explanation:
I am pretty sure it is B as the speed is obviously constant but the velocity is not constant as it defines as the rate of speed AND DIRECTION meaning that it is not constant as it always changes direction. And angular velocity is constant.
A circular loop of radius 13 cm carries a current of 13 A. A flat coil of radius 0.94 cm, having 58 turns and a current of 1.9 A, is concentric with the loop. The plane of the loop is perpendicular to the plane of the coil. Assume the loop's magnetic field is uniform across the coil. What is the magnitude of (a) the magnetic field produced by the loop at its center and (b) the torque on the coil due to the loop
Answer:
[tex]6.28\times 10^{-5}\ \text{T}[/tex]
[tex]1.92\times 10^{-6}\ \text{Nm}[/tex]
Explanation:
[tex]\mu_0[/tex] = Vacuum permeability = [tex]4\pi 10^{-7}\ \text{H/m}[/tex]
[tex]I_l[/tex] = Current in circular loop = 13 A
[tex]r_l[/tex] = Radius of circular loop = 13 cm
[tex]N[/tex] = Number of turns = 58
[tex]r_c[/tex] = Radius of coil = 0.94 cm
[tex]I_c[/tex] = Current in coil = 1.9 A
[tex]\theta[/tex] = Angle between loop and coil = [tex]90^{\circ}[/tex]
Magnitude of magnetic field in circular loop
[tex]B_l=\dfrac{\mu_0I_l}{2r_l}\\\Rightarrow B_l=\dfrac{4\pi 10^{-7}\times 13}{2\times 13\times 10^{-2}}\\\Rightarrow B_l=6.28\times 10^{-5}\ \text{T}[/tex]
The magnetic field produced by the loop at its center is [tex]6.28\times 10^{-5}\ \text{T}[/tex].
Torque is given by
[tex]\tau=\pi NI_cr_c^2B_l\sin\theta\\\Rightarrow \tau=\pi 58\times 1.9\times (0.94\times 10^{-2})^2\times 6.28\times 10^{-5}\sin90^{\circ}\\\Rightarrow \tau=1.92\times 10^{-6}\ \text{Nm}[/tex]
The torque on the coil due to the loop [tex]1.92\times 10^{-6}\ \text{Nm}[/tex].
For each of the following scenarios, describe the force providing the centripetal force for the motion: (Be very specific, and give some reasoning to your answer.) a. a car making a turn b. a child swinging around a pole c. a person sitting on a bench facing the center of a carousel d. a rock swinging on a string e. the Earth orbiting the Sun.
Answer:
a) tires rubbing, b) the weight has a component parallel to the floor
c) he child's back support, d) The tension of the rope and weight
Explanation:
In this exercise, we are asked to indicate the origin of the forces for the centripetal movement parallel to the rope, e) gravitational force
a) When a car turns, the centripetal force has two origins
* The tires rubbing against the road
* If the road has a lean angle, the component of the weight directed towards the center of the circle also contributes to the centripetal force.
b) the child in general has some degree of inclination with respect to the post, for which the weight has a component parallel to the floor that is responsible for the centripetal movement of the system
c) The bench rotates together with the carousel, so the child's back support is the response to the centripetal force
d) The tension of the rope has two components: the component perpendicular to the movement and the component of the weight (parallel to the rope) the difference of these two forces is the centripetal force
e) The gravitational force of the sun on the earth is what creates the centripetal motion
Calculate the volume occupied by a glass cup having a mass of 260 g knowing that the
density of glass is equal to 2.6 g/cm3
Answer:
100 milliliters
Explanation:
What is one benefit to measuring your body’s flexibility?
A.
meeting the national requirement for flexibility
B.
determining your muscular strength
C.
tracking your flexibility improvements over time
D.
increasing the length of your life
Answer:
C
Explanation:
if you measure your body's flexibility then you can keep track of how flexible you have gotten over time
It has been shown that the half-life for this radioactive isotope is 20 years. In the year 2000, an archaeology team unearths pottery and is using this isotope for radiometric dating to place the age of the pottery. It is shown that 95% of the nuclei have decayed. How much mass has decayed? How much mass is left?
I'd prefer to be shown a step-by-step on how to solve for these questions. I do better with seeing the step-by-step, and can retain the information better.
Answer:
(1/2)*n = .05 by the definition of half-life where n is the number of half-lives
n ln .5 = ln .05
n = ln .05 / ln .5 = 4.32 number of half-lives
So 4.32 * 20 = 86.4 years has passed
Actually, they only want the mass left. However, all that has changed is that
95% of the original radioactive atoms have changed to a different form of about the same amount of mass. The amount of mass remaining would be about the same. Also, one doesn't know the percentage of radioactive atoms
that formed the original mass.
1 ) when a ball is projected upwords its time of rising is ...............the time of falling .
a) greater than b) smaller than c) equal to d ) double
2 ) when an object falls freely under the effect of gravity , the distance moved is
a ) directly proportional to time
b ) inversely proportional to time
c ) directly proportional to square of time
d ) inversely proportional to square of time.
Answer:
correct answer is C
Explanation:
In this exercise, you are asked to complete the sentences so that the sentence makes sense.
1) in projectile launching, the only force that acts is gravity in the vertical direction, so the time of going up is EQUAL to the time of going down
correct answer C
2) when a body falls freely, the acceleration is the ratio of gravity, therefore if it starts from rest, its height is
y = v₀ t - ½ gt²
v₀ = 0
y = -1/2 g t²
so the position is not proportional to the square of the time
correct answer is C
Part D
How do supersonic flights create sonic boom? Please explain in detail.
Answer: A sonic boom is a sound associated with shock waves created when an object travels through the air faster than the speed of sound. Sonic booms generate enormous amounts of sound energy, sounding similar to an explosion or a thunderclap to the human ear. The crack of a supersonic bullet passing overhead or the crack of a bullwhip are examples of a sonic boom in miniature. Sonic booms due to large supersonic aircraft can be particularly loud and startling, tend to awaken people, and may cause minor damage to some structures. They led to prohibition of routine supersonic flight over land. Although they cannot be completely prevented, research suggests that with careful shaping of the vehicle, the nuisance due to the sonic booms may be reduced to the point that overland supersonic flight may become a feasible option. A sonic boom does not occur only at the moment an object crosses the speed of sound; and neither is it heard in all directions emanating from the supersonic object. Rather the boom is a continuous effect that occurs while the object is travelling at supersonic speeds. But it affects only observers that are positioned at a point that intersects a region in the shape of a geometrical cone behind the object. As the object moves, this conical region also moves behind it and when the cone passes over the observer, they will briefly experience the boom.
Explanation:
As incredible as the Concorde was, the sonic booms created by its supersonic flights were so disruptive that most countries restricted or completely prohibited the aircraft from flying over land. The sonic boom, at its worst, would be heard as a very loud thunder clap that was right overhead. The force of the boom rattled windows and loosened roof tiles. But even when the sonic boom sounded like a “softer” distant thunder clap, it was distracting to people and caused disruption of sleep and interruptions in activity. Imagine that you are driving on your way to work, and with clear skies overhead, you suddenly hear the sound of thunder. Your immediate responses are most likely surprise, shock, and an instinctive search for the source. Being caught by surprise in certain situations is rather annoying, and in others, potentially dangerous. In 1964, the FAA and NASA conducted a six-month sonic boom research project in Oklahoma City – without warning residents beforehand. The experiment consisted of eight sonic booms, every day, for six months. 15,000 complaints and a class action lawsuit were filed. The government lost on appeals. Great idea, guys, just brilliant. When the Concorde was originally designed, in the early 1960s, governments and airlines around the world lined up to place orders. The plane did an around-the-world publicity trip, and was well-received. But as awareness of the sonic boom effect grew, almost every country banned the aircraft. Only the US, Great Britain, and France allowed the Concorde to enter their airspace, and then only to cities in close proximity to the ocean – NYC, London, Paris, and Washington, DC. The Concorde was specifically designed for supersonic flight (specifically, Mach 2) and was very fuel-inefficient at subsonic speeds (less than Mach 1). Unfortunately, it was thus not feasible to fly at supersonic speed over water and then at subsonic speed over land.
What causes a sonic boom?
When any object moves, it creates waves in front of and behind it. Think of the waves that a boat creates at its bow and stern. In front, the waves are compressed together as the boat sails forward. Behind, the waves spread out away from the boat. In this case, you only see the waves on the surface of the water, and it appears two-dimensional. Similar principles are at play with aircraft. In front of the nose of a plane, air is pushed together and compressed as the aircraft flies forward. Behind the plane, the air creates waves that radiate out and away in the shape of a cone – three-dimensionally.
Answer:
A sonic boom is caused by the shock waves created when an object travels through the air faster than the speed of sound.
Explanation:
When any object moves, it creates waves in front of and behind it. Think of the waves that a boat creates at its bow and stern. In front, the waves are compressed together as the boat sails forward. Behind, the waves spread out away from the boat. Similar principles are at play with aircraft. In front of the nose of a plane, air is pushed together and compressed as the aircraft flies forward. Behind the plane, the air creates waves that radiate out and away in the shape of a cone – three-dimensionally. Things get interesting, and complicated, when you fly faster than the speed of sound – supersonic flight. The nose of a supersonic aircraft pushes ahead of its forward waves. These waves get in the way of the airplane, causing compression which results in a shock wave. Actually, this creates two shocks, one forming as the aircraft passes the front of the wave and then another as it leaves the wave. The shock wave generated stays mostly behind the aircraft, and radiates out in a cone
A magnetic field is passing through a loop of wire whose area is 0.014 m^2. The direction of the magnetic field is parallel to the normal to the loop, and the magnitude of the field is increasing at the rate of 0.19 T/s.
a. Determine the magnitude of the emf induced in the loop.
b. Suppose the area of the loop can be enlarged or shrunk. If the magnetic field is increasing as in part (a), at what rate (in m^2/s) should the area be changed at the instant when B = 1.6 T if the induced emf is to be zero? (Give the magnitude of the rate of change of the area.) (m^2/s). Explain whether the area is to be enlarged or shrunk.
Answer:
a. 0.00266v
b. -0.0016625
the area should be shrunk
Explanation:
the magnitude of the EMF induced in the loop
= area * rate
= 0.014 * 0.19
= 0.00266 V
B we are to solve for the rate at which the are has to be change with B = 1.6
δA/δt = -A/B * dB/dt
= (-0.014 * 0.19) /1.6
= -0.0016625
the sign is negative so the EMT is negative and so the area has to be shrunk.