1.61 x 10^29 molecules of air are needed to fill the auditorium at one atmosphere and 0°C.
To determine how many molecules of air are needed to fill an auditorium with a volume of 6 x 10^3 m^3 at one atmosphere and 0°C, we can use the Ideal Gas Law formula:
PV = nRT
Where:
P = pressure (1 atm)
V = volume (6 x 10^3 m^3)
n = number of moles of air
R = ideal gas constant (0.0821 L atm / K mol)
T = temperature in Kelvin (273 K, since 0°C = 273 K)
First, convert the volume from m^3 to liters by multiplying by 1000:
V = 6 x 10^3 m^3 * 1000 = 6 x 10^6 L
Now, rearrange the Ideal Gas Law formula to solve for the number of moles (n):
n = PV / RT
Plug in the values:
n = (1 atm) (6 x 10^6 L) / (0.0821 L atm / K mol) (273 K)
Calculate the result:
n ≈ 2.68 x 10^5 moles of air
To find the number of molecules, multiply the moles of air by Avogadro's number (6.022 x 10^23 molecules/mol):
Number of molecules = 2.68 x 10^5 moles * 6.022 x 10^23 molecules/mol
Number of molecules ≈ 1.61 x 10^29 molecules
So, approximately 1.61 x 10^29 molecules of air are needed to fill the auditorium at one atmosphere and 0°C.
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What must the charge (sign and magnitude) of a 3.45 g particle be for it to remain stationary when placed in a downward-directed electric field of magnitude 590 N/C
charge must be equal to 5.74 ×10⁻⁵
In the question it is said that the particle remains stationary which means the the net force on the particle is zero. So, the counterbalancing forces must be equal which means weight is equal to upward electric force.
→ Fnet =0
→ mg = qE
substituting the values we get :
0.00345 × 9.81 = q × 590
→ q = 5.74 ×10⁻⁵
Hence the charge must be equal to 5.74 ×10⁻⁵.
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When a voltage of 12 V is applied to a resistor, a current of 2.5 A passes through it. What is the resistance of the resistor
Answer:
4.8 Ω
Explanation:
Ohm's law
V = IR
or V/I = R
12/2.5 = R = 4.8 Ω
Two parallel wires are separated by 0.36 m. Wire A carries 4.8 A and Wire B carries 8.9 A, both currents in the same direction. The force on 0.53 m of Wire A is:
The force on 0.53 m of Wire A is 1.3×10^(-5) N.
To find the answer, we need to know about the force on a current carrying wire due to another parallel wire.
What's the force experienced by a current carrying wire of length L due to another current carrying parallel wire?The magnetic force experienced by the wire here= μ₀IAIBL/(2πr)IA= current in wire A, IB= current in wire B, L = length of wire and r= separation between themWhat's the force on 0.53 m of Wire A, if IA, IB, L and r are 4.8A, 8.9A, 0.53m and 0.36 m respectively?Force = (4π×10^(-7)×4.8×8.9×0.53)/(2π×0.36)
= 1.3×10^(-5) N
Thus, we can conclude that the force on 0.53 m of Wire A is 1.3×10^(-5) N.
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You are singing a song at karaoke and reach a part that requires a louder, more intense sound. What must you do to produce a louder sound
More energy is used in creating a louder sound from the mouth.
What must you do to produce a louder sound?We use more energy in order to produce a louder sound because energy is the thing that helps in the formation of loud sound. Loudness is dependent on the energy that creates loud sound in the mouth. More energy we apply, more loud sound will produce. Energy is the main factor which gives us a loud sound in each and every instruments. Without, we can't imagine loud sound.
So we can conclude that more energy is used in creating a louder sound from the mouth.
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A force does work on an object if a component of the force __________.
Group of answer choices
a. is parallel to the displacement of the object
b. is perpendicular to the displacement of the object
c. perpendicular to the displacement of the object moves the object along a path that returns to its starting point
d. parallel to the displacement of the object moves the object along a path that returns to its starting point
Option A. A force does work on an object if a component of the force is is parallel to the displacement of the object.
Work done by force
The force applied to an object to displace it from a given point to another point is known as work done on the object.
W = Fd cosθ
where;
f is the magnitude of applied forced is the displacement of the object.θ is the angle between the applied force and displacement.Thus, A force does work on an object if a component of the force is is parallel to the displacement of the object.
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Consider vectors u and v, where u = ⟨1, –1⟩ and v = ⟨1, 1⟩. what is the measure of the angle between the vectors?
The angle between the two vectors is 0⁰, thus the two vectors are parallel to each other.
Angle between the vectorsThe angle between the vectors describes the direction of the vector and the value of the angle can be determined from the horizontal and vertical components of the vectors as shown below.
The sum of the horizontal components and vertical components of the vectors is calculated as follows;
Sum of the horizontal component of the vectors, x = 1 + 1 = 2
Sum of the vertical component of the vectors, y = -1 + 1 = 0
The angle between the vectors is calculated as follows;
θ = arc tan (y/x)
θ = arc tan (0/2)
θ = arc tan (0)
θ = 0⁰
The angle between the two vectors is 0⁰, thus the two vectors are parallel to each other.
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Answer: C. 90°
Explanation:
A stone ‘X’ of mass 2 kg is at the height of 20m in two minutes, calculate the power delivered. [g=10 m/s-2]
400 J power will be delivered by lifting a stone of mass 2 kg at the height of 20m in two minutes.
What is power?The quantity of energy transferred or transformed per unit of time is known as power. The watt, or one joule per second, is the unit of power in the International System of Units. Power is also referred to as an activity in ancient writings. A scalar quantity is a power.
Work completed and time is linked in the power equation. Since forces may move objects and we know that forces perform work, we might anticipate that by understanding the power, we can gain insight into how a body moves through time. This outcome may be especially beneficial.
Given that, a stone ‘X’ of mass 2 kg is lifted to the height of 20m in two minutes, and g=10 m/s-2
Power Delivered = Work done in lifting the stone
Work Done = Potential energy = mgh
Work done = 2 × 10 × 20
Work done = 400 J
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When a person is standing upright, the weight of anything being lifted and carried in the hands is first reflected onto the:
Pelvic girdle
In human anatomy, the pelvis is a complex of bones that connects the trunk and the legs, supports and balances the trunk, and houses and supports the intestines, the urinary bladder, and the internal organ. It is sometimes referred to as the bony pelvis or the pelvic girdle.
One is located on the left side of the body and the other is located on the right. They come together to make the pelvic girdle, a portion of the pelvis. The hip bones are attached to the upper portion of the skeleton at the sacrum.
The pelvic girdle's main function is to support the upper body's weight while seated and transfer that weight to the lower limbs while standing. For the muscles in the trunk and lower limbs, it functions as attachment point.
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physical and chemical properties of water
(Not sure how many examples you need so I will put three for each)
Physical:
Chemical:
One of the most significant characteristics of water is its amphoteric tendency. Amphoteric refers to a substance's capacity to function as an acid or base. Water is neither acidic nor basic in its natural form. Its capacity to give and receive protons is the key justification. However, rainfall has a pH between 5.2 and 5.8, making it mildly acidic.Water is referred to be the all-purpose solvent. This is due to its chemical makeup, physical characteristics, high dielectric constant, and other factors that make it the most solvent material. It can attract other compound molecules, disabling their molecular forces and causing them to dissolve since hydrogen and oxygen both have positive and negative charges that are available.Water is a chemical molecule made up of two hydrogen atoms and one oxygen atom. The liquid condition of that substance is often referred to as water, and the solid and gas phases are respectively referred to as ice and steam.A plastic rod is charged up by rubbing a wool cloth, and brought to an initially neutral metallic sphere that is insulated from ground. It is allowed to touch the sphere for a few seconds, and then is separated from the sphere by a small distance. After the rod is separated, the rod:.
After the rod is charged and then touched on the neutral metallic sphere and then separated from it, the rod is repelled by the sphere. Option A
What is a static charge?There are very ways in which a static charge could be built up in an object. The ways include;
FrictionElectrostatic induction and ContactNow, after the rod is charged and then touched on the neutral metallic sphere and then separated from it, the rod is repelled by the sphere.
Missing parts;
A plastic rod is charged up by rubbing a wool cloth, and brought to an initially neutral metallic sphere that is insulated from the ground. It is allowed to touch the sphere for a few seconds, and then is separated from the sphere by a small distance. After the rod is separated, the rod
A. is attracted by the sphere
B. is repelled by the sphere
C. feels no force due to the sphere
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An astronomical telescope is designed with over magnification of 35x if the object has a focal length of 100 cm what should be the focal length of the eyepiece and how far should the eyepiece be from the objective
The focal length of eyepiece is 2.85.
It is given that astronomical telescope is designed with over magnification of 35.
The object has a focal length of 100 cm.
We need to determine the focal length of the eyepiece.
The formula to be used here is for astronomical telescope is:
[tex]m=\frac{f_{0} }{f_{e} }[/tex]
Using values here, we get
[tex]35=\frac{100 }{f_{e} }[/tex]
[tex]f_{e}=100/35=2.85[/tex]
Hence, the focal length of eyepiece is 2.85
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Which of the following is an advantage of recorded presentations? A. Start-times and time zones are not a factor. B. Speakers can adapt topic coverage if necessary. C. Audience members have the opportunity to provide feedback D. More visual aids can be used.
The statement describes an advantage of recorded presentations is that the audience members have the opportunity to provide feedback. Thus, the correct option for this question is C.
What do you mean by Recorded presentations?A recorded presentation may be defined as a popular format of multimedia content with a duration of several seconds or minutes that significantly expresses the advantages of a product, service, or any idea with the support of interesting graphic images, concise text, and appropriate narration.
According to the context of this question, a recorded presentation delivers an advantage to the audience to provide feedback. This is because the process of recorded PowerPoint presentation gives the actual sense and understanding to the audience similar to the real event.
Therefore, the correct option for this question is C.
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What was Kobe’s attitude toward life and competition?
Answer: Positive
Explanation: Kobe has had an positive attitude on situations and life itself. No matter the competition he still kept a positive attitude regardless. He still wished the best for others even if his enemies thought otherwise. So Kobe was a positive person on the outlook of life and competition.
A 36.5-g glass thermometer reads 23.6 ∘C before it is placed in 145 mL of water. When the water and thermometer come to equilibrium, the thermometer reads 40.8 ∘C. Ignore the mass of fluid inside the glass thermometer. The value of specific heat for water is 4186 J/kg⋅C∘, and for glass is 840 J/kg⋅C∘.
The initial temperature of the water was [tex]41.6688^{0} C[/tex].
Given,
Weight of glass 36.5g
specific heat for glass is 840 J/kg⋅C∘.
Initial temperature of glass was [tex]23.6^{0} C[/tex].
Weight of water is 145*1=145g (Density*Volume=145ml*1g/ml)
Temperature final was [tex]40.8^{0} C[/tex].
specific heat for water is 4186 J/kgâ‹…Câˆ
(m of glass)(Cp of glass)(Tf_glass-Ti_glass) = (m of water)(Cp of water)(Ti_water - Tf_water)
36.5*840*(40.8-23.6)=145*4186*(Ti_water - 40.8)
Ti_water=[tex]41.6688^{0} C[/tex]
Specific heatIn thermodynamics, a material's specific heat capacity, or massic heat capacity as it is sometimes known, is equal to the heat capacity of a sample of the substance divided by the mass of the sample (symbol cp). Informally, it is the quantity of heat needed to raise a substance's temperature by one degree for every unit of mass that is added to it. joule per kelvin per kilogram, or Jkg1K1, is the SI unit for specific heat capacity. For instance, the amount of energy needed to increase the temperature of 1 kilogram of water by 1 K is 4184 joules, making water's specific heat capacity 4184 J kg 1 K 1.
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The spectral type of this star is listed as K5V. (V means it is a main sequence star.) Based on the table below, how does the surface temperature of this star compare with that of HIP 87937
It turns out that the star in question belongs to the K5V star class. Thus, the surface temperature of this must be between 5200 K and 3700 K. It has a surface temperature of 6200 K to 5200 K and is a G2V class star, commonly known as Bernard's star. In other words, the star in question has a colder surface than HIP 87937. This is further explained below.
What is surface temperature?Generally, The temperature at a surface is referred to as the surface temperature. In particular, it may refer to the surface air temperature, which is the temperature of the air that is relatively close to the earth's surface.
In conclusion, The star in question is of the K5V type. Therefore, the temperature of the surface of this must be somewhere between 5200 and 3700 kelvin. The star with the designation HIP 87937, often known as Bernard's star, is of the G2V type. Stars of this type have a surface temperature that falls anywhere between 6200 and 5200 degrees Celsius. Therefore, it should come as no surprise that the surface temperature of the given star is lower than that of HIP 87937.
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Answer: It is hotter because K is before M
Explanation:
The actual surface temperature of this star is 4600 KK compared to 3100 KK for the M4 star in Parts A and B.
A uniform bar 15m long balanced on a pivot at its midpoint. A boy of mass 55kg sits on one arm of the bar at a point 5m away from the pivot. What mass can be placed 2m away from the other end of the bar to keep the bar horizontally
The mass at the other end of bar will be 50g .
what is mass
It is the fundamental property of matter , every single property which exist in this world has mass
Mass never can be 0 .
So , the system is in equilibrium
let mass of the body be m
55×5= m×5.5
m= 5 5 × 5 /. 5.5
m= 5 0g
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137.5 kg mass can be placed 2m away from the other end of the bar to keep the bar horizontally.
What does horizontal mean?Any straight line traveling from left to right or right to left is a horizontal line. If two points on a line share the same Y-coordinates, the line is said to be horizontal in coordinate geometry. It is derived from the word "horizon." In other words, the horizon or x-axis is always parallel to the horizontal lines.In the coordinate plane, a horizontal line is a straight line drawn from right to left or from left to right, perpendicular to the x-axis. In other words, a horizontal line is a straight line with an intercept solely on the y-axis, not the x-axis.To keep the bar horizontal, the right and left side torques must be equal:
[tex]F_{1} d_{1} =F_{2} d_{2}[/tex]
[tex]F_{2} =F_{1} \frac{d_{1} }{d_{2} }[/tex]
[tex]=(55.9.8)\frac{5}{2}[/tex]
=1347.5 N.
Convert this force of gravity into mass:
[tex]F_{2} =m_{2} g,[/tex]
[tex]m_{2} =\frac{F_{2} }{g}[/tex]
[tex]=\frac{1347.5}{9.8}[/tex]
=137.5 kg.
The answer is 137.5 kg.
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Why is quantum computing potentially a better fit for weather forecasting than classical computers?.
Quantum computing is a better fit than classical computing because it can access advanced simulations for vast quantities of weather.
What is Quantum computing?
Quantum computing can process large number of data sets of weather for all the properties of quantum states. Unlike classical computers which contains only standard bits 0 and 1 , quantum computing use Qubit or Quantum bit in which there are more than two standard sets of bits. These Qubits can measure the light at any degrees of polarisation between 1 and 0.This is the spin attribute that corresponds to superposition. This can create a lot more possibilities beacuse we can run multiple tasks at once with only one bit of data beacuse of the superpositioned qubit. This unlike classical computers where the bit can be only 1 and 0 is more effectively used in breaking encryption tasks.
So, the analysis of vast quantities of weather data can be done in seconds using Quantum computing.
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A lightning strike can transfer as much as electrons from the cloud to the ground. if the strike lasts 2ms , what is the average electric current in the lightning?
The average electric current in the lightning will be 8 × [tex]10^{-17}[/tex] A
Why Lightning Conductors on top of a tower ?The lightning conductors are long metal strips running from the spike end of a conductor on the top of a building to the earth. They are used to prevent buildings from destruction when struck by thunder or lightning.
Given that a lightning strike can transfer as much as electrons from the cloud to the ground. if the strike lasts 2ms, to calculate the average electric current in the lightning, we will first consider the charge released.
one charge = 1.6 × [tex]10^{-19}[/tex] C
Average current I = Q/t
Where
Q = charge = 1.6 × [tex]10^{-19}[/tex] Ct = time = 2ms = 2 × [tex]10^{-3}[/tex] sI = current = ?Substitute all the parameters into the formula
I = 1.6 × [tex]10^{-19}[/tex] C ÷ 2 × [tex]10^{-3}[/tex]
I = 8 × [tex]10^{-17}[/tex] A
Therefore, the average electric current in the lightning will be 8 × [tex]10^{-17}[/tex] A
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Why stars are shows like twinkling in the sky’s!
Reply please!
Answer:
As light from a star races through our atmosphere, it bounces and bumps through the different layers, bending the light before you see it. Since the hot and cold layers of air keep moving, the bending of the light changes too, which causes the star's appearance to wobble or twinkle.
An astronomy student, for her PhD, really needs to estimate the age of a cluster of stars. Which of the following would be part of the process she would follow
Plotting what is referred to as an H-R diagram for the stars in the cluster is part of the process in which the astronomy student will follow in this type of scenario.
What is H-R diagram?This is referred to as the Hertzsprung–Russell diagram and is a scatter plot which depicts the relationships between stars' absolute magnitudes versus their effective temperature. It can also be inferred that the higher the luminosity of a star, the higher the temperature and vice versa.
This helps to depict stellar evolution as a result of the features used as parameters such as the life cycle as an older star will be less luminous when properly studied by people hereby making it easier to estimate the age of stars.
This therefore the reason why plotting a Hertzsprung–Russell diagram is very important.
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It is advisable to place room heater at the ground level for effective heating
Answer:
yes
Explanation:
The heater is placed near the floor because the air currents move upwards so the hot air fills up the whole room. Whereas, an air conditioner is placed near the ceiling because the cold breeze tends to settle down. If it is placed near the floor then it will fill just the bottom of the room with cool air.
What information do we know about the known exoplanets? a. estimates of orbits and masses b. complete composition c. precise masses d. all of the above e. none of the above
The correct option is A. The information we know about the known exoplanets is estimates of orbits and masses.
What is exoplanets?An exoplanet or extrasolar planet is a planet outside the Solar System.
In other words, exoplanet is any planet beyond our solar system.
Characteristics of exoplanetsexoplanets are known for the following characteristics;
they are usually hotthey can orbit their stars so tightly that a “year” lasts only a few daysthey can orbit two suns at onceThus, the information we know about the known exoplanets is estimates of orbits and masses.
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What was the role of gravity in the formation of the solar system?
A. Gravity caused the solar system to move closer to the Sun.
OB. Gravity caused the solar system to compress into one larger
mass.
OC. Gravity caused the solar system to separate into individual
celestial bodies.
D. Gravity caused the solar system to expand from a central point.
The role of Gravity in the formation of the solar system is that gravity caused the the solar system to move closer to the Sun.
This was possible because gravity attracted smaller particles together until they formed large particles and began to rotate around the sun.
What is Gravity?Gravity is the force by which a planet or other body draws objects toward its center. The force of gravity keeps all of the planets in orbit around the sun.
Gravity can also be said to mean an attraction between objects objects with mass.
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what is the best fuse for 1000 w heater?
a)3A
b)4A
c)5A
d)11A
c)5A
Explanation:
As,
[tex]I = \frac{P}{V} = \frac{1000}{220} = 5[/tex]
Excessive use of fossil fuels causes an energy crisis
yes, it causes an energy crisis. Burning Fossil Fuels
When we burn oil, coal, and gas, we don't just meet our energy needs, we move the current global warming crisis as well.
Fossil fuels produce large amounts of carbon dioxide when burned. Carbon emissions trap heat in the air and lead to climate change.
What are the major causes of energy crisis?
Most energy crises have been caused by localized shortages, wars and market manipulation. Some have argued that government efforts like tax hikes, nationalization of energy companies, and rule of the energy sector, shift supply and demand of energy away from its economic stability.
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The spectral type of this star is B7V. The order of spectral types, from hottest to coolest, is OBAFGKM. How does the surface temperature of this star compare with the other stars we have observed
The hottest celebrity is this one.
The majority of stars fall under a select few spectral categories. The hottest to the coldest stars are listed in the spectral types of the Henry Draper and Bright Star Catalogues (see stellar classification). The letters O, B, A, F, G, K, and M are used to indicate these categories in decreasing order of temperature.
What is Spectral type of star ?Using spectral types, we can categorise stars based on their colour or the spectral lines that are visible in their light. The spectral types are OBAFGKM, with the hottest stars being O and the coldest being M. To humans, cooler stars appear redder and hotter stars appear bluer.
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A large box is being pushed across the floor at a constant speed of 4.0 m/s. What can you conclude about the forces acting on the box?
There is no force acting on the large box.
What is the force according to Newton's law?According to Newton's second law of motion, Force is defined as the rate of change of momentum with respect to time.Mathematically, force = mass × accelerationAnd acceleration = velocity/ timeHere, the large box is moving with constant velocity. So its velocity is not changing with time.So velocity / time = zero i.e. acceleration= zeroIt leads to the force to be zero.Thus, we can conclude that the force on the large box is zero.
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Pearl labels a diagram of a charged capacitor as shown. Which change would correct the error in the diagram?
A) changing +2Q to +Q
B) changing +2Q to –2Q
C) reversing the direction of the arrows
D) reversing the labels for Conductors and Insulator
To correct the error in the diagram, we need to change +2Q to +Q in order for the charges to become balanced. Option A
What is a capacitor?A capacitor is device that is used for storing electric charge. We know that the capacitor is composed of two conductors separated by an insulator.
In order to correct the error in the diagram, we need to change +2Q to +Q in order for the charges to become balanced. Option A
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Answer:
A
Explanation:
Monochromatic light with wavelength 590 nm passes through a single slit 2. 30 ?m wide and 1. 90 m from a screen. Find the distance between the first- and second-order dark fringes on the screen.
Answer:
The fringes are 4.7*10^-7 m apart, such that they are adjacent.
Explanation:
Using the formula for adjacent fringes given a single slit:
Δ[tex]x=\frac{(Wavelength)(Distance between slit and screen)}{Width}[/tex]
Δ[tex]x=\frac{(590/10^{9})(1.90) }{(2.30)}[/tex]
Δ[tex]x=0.000000487 m[/tex]
Hope this helps!
The distance between the first-order and second-order dark fringes on the screen will be 4.874 × 10⁻⁵ cm.
Given:
wavelength, λ = 590 nm = 590 × 10⁻⁹ m
Distance between the slit and screen, D = 1.90 m
Width of slit, d = 2.30 m
Calculation:
We know that the distance between two slits is given as:
Δx = λD / d
where λ is the wavelength of light
D is the distance between the slit and screen
d is the width of the slit
Applying values in the above equation we get:
Δx = (590 × 10⁻⁹ m)(1.90 m) / (2.30 m)
= 4.874 × 10⁻⁷ m
= 4.874 × 10⁻⁵ cm
Therefore, the distance between the first- and second-order dark fringes on the screen will be 4.874 × 10⁻⁵ cm.
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A 540 gram object is attached to a vertical spring, causing the spring’s length to change from 70 cm to 110 cm.
What is the spring constant k?
Group of answer choices
130 N/m
33 N/m
13 N/m
330 N/m
Answer:
Approximately [tex]13\; {\rm N \cdot m^{-1}}[/tex] (assuming that [tex]g = 9.81\; {\rm N \cdot kg^{-1}}[/tex].)
Explanation:
Let [tex]F_{\text{s}}[/tex] denote the force that this spring exerts on the object. Let [tex]x[/tex] denote the displacement of this spring from the equilibrium position.
By Hooke's Law, the spring constant [tex]k[/tex] of this spring would ensure that [tex]F_\text{s} = -k\, x[/tex].
Note that the mass of the object attached to this spring is [tex]m = 540\; {\rm g} = 0.540\; {\rm kg}[/tex]. Thus, the weight of this object would be [tex]m\, g = 0.540\; {\rm kg} \times 9.81\; {\rm N \cdot kg^{-1}} \approx 5.230\; {\rm N}[/tex].
Assuming that this object is not moving, the spring would need to exert an upward force of the same magnitude on the object. Thus, [tex]F_{\text{s}} = 5.230\; {\rm N}[/tex].
The spring in this question was stretched downward from its equilibrium by:
[tex]\begin{aligned} x &= (70\; {\rm cm} - 110\; {\rm cm}) \\ &= (-40)\; {\rm cm} \\ &= (-0.40) \; {\rm m}\end{aligned}[/tex].
(Note that [tex]x[/tex] is negative since this displacement points downwards.)
Rearrange Hooke's Law to find [tex]k[/tex] in terms of [tex]F_{\text{s}}[/tex] and [tex]x[/tex]:
[tex]\begin{aligned} k &= \frac{F_{\text{s}}}{-x} \\ &\approx \frac{5.230\; {\rm N}}{-(-0.40)\; {\rm m}} \\ &\approx 13\; {\rm N \cdot m^{-1}}\end{aligned}[/tex].