Doing contracting work for government agencies of private businesses
The mission control center is a facility that is responsible for controlling and coordinating the operations of a spacecraft during a mission. It is typically run by NASA or another space agency and is used to monitor and communicate with spacecraft, as well as to plan and execute mission objectives. The mission control center is not typically involved in contracting work for government agencies or private businesses.
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The same 42 kg cart is pushed forward with a force of 180 Newtons. How far will it go if a total of 2500 Joules of work are done on the cart?
Important Formulas:
[tex]w=Fd[/tex]
work(measured in joules) = force(measured in newtons) * distance(measured in meters)
__________________________________________________________
Given:
[tex]m=42kg[/tex]
[tex]F=180N[/tex]
[tex]w=2500J[/tex]
[tex]d=?[/tex]
__________________________________________________________
Rearranging work formula to make distance the subject:
[tex]w=Fd[/tex]
[tex]\dfrac{w}{F} =\dfrac{Fd}{F}[/tex]
[tex]d=\dfrac{w}{F}[/tex]
__________________________________________________________
Finding distance:
[tex]d=\dfrac{w}{F}[/tex]
[tex]d=\dfrac{2500}{180}[/tex]
__________________________________________________________
[tex]\fbox{d = 13.89 meters}[/tex]
what is the normal force on a 2000N refrigerator resting on the ground
The perpendicular force that a surface applies to an item is known as the normal force. FN = m ⋅ g
What is Normal force?The perpendicular force that a surface applies to an item is known as the normal force. For instance, if you place a book on a table, a gravitational force will cause it to fall. The table pulls on the book in order to counterbalance this force and keep it from dropping. The normal force, often known as the opposing force, is denoted by the symbols FN F N or NN. "N" stands for the normal force unit (Newton).
A common illustration of Newton's third rule of motion is the normal force.
When one object applies force to another, the other applies a force in the opposite direction and of equal magnitude to the first object (action equals reaction).
Therefore, the force applied by the item to the surface is equal to the normal force. The calculations change according to the surface's slope.
The formula is as follows for an object laying on a flat surface:
FN = m ⋅ g
where
The mass of an object is m.
Gravitational acceleration is denoted by g.
The normal force (FN F N ) for an item on a flat surface is equal to its gravitational force, according to Newton's third law ( WW).
The formula is as follows for an object laying on a flat surface:
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A model rocket flies horizontally off the edge of a cliff at a velocity of 50.0 m/s. If the canyon below is 100.0 m deep, how far from the edge of the cliff does the model rocket land?
My teacher provided the equations:
x= vt and y = (Vi * t)1/2* a * t^2
Yes! The second one is one of the constant acceleration equations. We know that our X and Y values are independent of each other, which is why Y doesn't matter here. We only care about the X position value since X and Y are independent! (This is an extremely important rule, trust me)
Therefore, we don't need to calculate a Y velocity or anything like that. We only need Y because we need to find time t. We can use Y to calculate time because although X and Y are independent of each other, they do share the same time traveled!
We know that [tex]V_{0,y}[/tex] = 0, since the car wasn't moving vertically initially. We also know Y initial is 100 and Y final is 0 when it hits the ground! The last thing we know is that the acceleration of any item in free fall is (usually) -9.81. Therefore, using the original Y equation that your teacher gave, we can plug things in and solve for time!
[tex]y_f=y_i+v_it+\frac{1}{2}at^2\\0=100+(0)t+\frac{1}{2}(-9.81)t^2\\-100=-4.905t^2\\t^2=20.39\\t=4.52[/tex]t = 4.52s
(Your teacher simplified the Y equation a little, so it may look slightly different from mine. I started at the original Y equation)
Now we have time! So now we can use the other equation your teacher provided. Again, remember, even though the car is now traveling through the air vertically, that does not affect its x velocity! The car is still traveling at 50m/s!
Therefore, we can just plug and chug!:
x = vt
x = (50)(4.52)
x = 226m
I hope this helps!
The bean of light is incident from a light source is: i.covergent
ii.divergent
iii.parallel
iv.both i and ii
Answer:
I think the answer is II.divergent
because parralel beams are convergent to the light source
and in the question it says incident from the light source
Answer:
The correct answer is (i) Convergent.
Add the following and give the answer using significant figures 5000+621
Answer:
;) hope it's helpful
Explanation:
5000 + 621 = 5621
Facts about 5621
Sig Figs
4
5621
Decimals
0
Scientific Notation
5.621 × 103
E-Notation
5.621e+3
Words
five thousand six hundred twenty-one
Robert Galstyan, from Armenia, pulled two coupled railway wagons a distance of 7 m using his teeth. The total mass of the wagons was about 2.20 X 10^5 kg. Of course, his job was made easier by the fact that the wheels were free to roll. Suppose the wheels are blocked and the coefficient of static friction between the rails and the sliding wheels is 0.220. What would be the magnitude of the minimum force needed to move the wagons from rest? Assume that the track is horizontal.
The magnitude of the minimum force needed to move the wagons from rest is 474320 N
How do I determine the force needed to move the wagons?We have come to know that the force and coefficient of friction have a simple relationship as shown by the equation below:
Frictional force (N) = coefficient of friction (μ) × normal reaction (N)
F = μN
Applying the above formula, we can determine the force needed to move the wagons from rest. Details below:
Mass of wagons (m) = 2.20×10⁵ KgAcceleration due to gravity (g) = 9.8 m/s²Normal reaction (N) = mg = 2.20×10⁵ × 9.8 = 2156000 NCoefficient of static friction (μ) = 0.220Force needed (F) = ?F = μN
F = 0.220 × 2156000
F = 474320 N
Thus, the force needed is 474320 N
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an object 50 cm high is placed 1 m in front of a converging lens whose focal length is 1.5 m. determine the image height (in cm).
Given :
An object 50 cm high is placed 1 m in front of a converging lens whose focal length is 1.5 m.
To Find :
the image height (in cm).
Solution :
By lens formula :
[tex]\dfrac{1}{v} - \dfrac{1}{u} = \dfrac{1}{f}[/tex]
Here, u = - 100 cm
f = 150 cm
[tex]\dfrac{1}{v} - \dfrac{1}{-100} = \dfrac{1}{150}\\\\v = - 300 \ cm[/tex]
Now, magnification is given by :
[tex]m = \dfrac{v}{u} = \dfrac{h_i}{h_o}\\\\h_i = \dfrac{300}{100}\times 1\\\\h_i = 3 \ m[/tex]
Therefore, the image height is 3 m or 300 cm.
An object located 32.0 cm in front of a lens forms an image on a screen 8.00 cm behind the lens. (a) Find the focal length of the lens. (b) Is the lens converging or diverging?
Answer: I don’t know someone tell me
Explanation: ^
Suppose that you wish to construct a simple AC generator with an output of 12 V maximum when rotated at 60 Hz. A magnetic field of 0.050 T is available. If the area of the rotating coil is 100 cm2, how many turns are needed?
Answer:
N = 63.6
Explanation:
The emf induced in AC generator is given as follows:
[tex]V = N\omega AB Sin\theta[/tex]
for maximum output, [tex]Sin\theta = 1[/tex]
[tex]V = N(2\pi f) AB[/tex]
where,
V = Maximum Output Voltage = 12 V
N = No. of Turns = ?
f = frequency = 60 Hz
A = Area of Coil = 100 cm² = 0.01 m²
B = Strength of Magnetic Field = 0.05 T
Therefore,
[tex]12\ V = N(2)(\pi)(60\ Hz)(0.01\ m^2)(0.05\ T)\\\\N = \frac{12\ V}{(2)(\pi)(60\ Hz)(0.01\ m^2)(0.05\ T)}[/tex]
N = 63.6
A hairdryer has a power of 1000W and was used for half an hour, how much did it cost with the energy price being 14p/kWh?
Answer:
12hp and 132 ml
Explanation:
12+ 132.00=12asd
PLZ HELP!!! BRAINLYEST WILL BE GIVEN TO BEST ANSWER!!!! IF YOU PUT A LINK I WILL REPORT YOU!!!!! DONT TRY ME!!!!!! YALL BEEN WASTING MY POINTS LATELY I HATE IT SO NO SNEAKY LINK OR NON ANSWER OR U WILL BE REPORTED.
Answer:
Explanation:
The corona is in the outer layer of the Sun's atmosphere—far from its surface. Yet the corona is hundreds of times hotter than the Sun's surface. ... In the corona, the heat bombs explode and release their energy as heat. But astronomers think that this is only one of many ways in which the corona is heated.
The chromosphere ("sphere of color") is the second of the three main layers in the Sun's atmosphere and is roughly 3,000 to 5,000 kilometers deep. Its rosy red color is only apparent during eclipses. The chromosphere sits just above the photosphere and below the solar transition region.
The photosphere is the visible "surface" of the Sun. The Sun is a giant ball of plasma (electrified gas), so it doesn't have a distinct, solid surface like Earth. ... The photosphere is much cooler than the Sun's core, which has a temperature well above 10 million degree
And thats all i know
Equilibrium exists in a system where three forces are acting concurrently on an object. If the system includes a 5.0-newton force due north and a 2.0-newton force due south, the third force must be?
The third force must be 3.0 newtons due north in order for equilibrium to exist in the system.
Why should equilibrium exist in system?This is so because the total of all the forces acting on the object equals the net force acting on it. The net force in this situation is 3.0 newtons due north and is calculated by subtracting the 5.0 newton force due north from the 2.0 newton force due south.In equilibrium, the net force on an object is zero.A chemical reaction is said to be in a state of north equilibrium when the reactant and product concentrations remain stable throughout time. The concentrations of the reactants and products stay unchanged, and the rate of the forward reaction is equal to the rate of the reverse reaction.To know more about equilibrium, check out :
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the air in a kitchen has pressure 1.0 x 10^5 Pa and temperature 22C. A refrigerator of internal volume 0.36 m^3 is installed in the kitchen. with the door open the air in the refrigerator is initially at the same temperature and pressure as the air in the kitchen. calculate the number of molecules of air in the refrigerator
You can answer this question using the equation PV = nkT, with the Boltzmann constant. This equation should come to mind since they listed every variable in the equation except for n, which is used to calculate the number of molecules!
Also note that temperature should be in Kelvin, so we should do a quick conversion!
K = 273 + C
K = 273 + 22
K = 295
Now we can plug and chug!
[tex]PV=nRT\\(1.0*10^5)(0.36)=n(1.38 * 10^{-23})(295)\\n=\frac{(1.0*10^5)(0.36)}{(1.38 * 10^{-23})(295)}\\n=8.84*10^{24}[/tex]
Therefore, there are 8.84E24 molecules of air in the refrigerator!
The number of molecules of air in the refrigerator is 14.67.
Given:
P = 1.0 x 10⁵ Pa
V = 0.36 m³
R = 8.314 J/(mol·K)
T = 295.15 K
To calculate the number of molecules of air in the refrigerator, the ideal gas law can be used, which states: PV = nRT
where:
P = pressure of the gas
V = volume of the gas
n = number of moles of gas
R = ideal gas constant
T = temperature of the gas
First, let's convert the temperature from Celsius to Kelvin:
T = 22°C + 273.15 = 295.15 K
Now, rearrange the ideal gas law equation to solve for the number of moles (n) of gas:
n = PV / RT
Substituting in the values:
[tex]n = \frac{1.0 \times 10^5 \times 0.36}{8.314 \times 295.15}\\[/tex]
n = 0.0001467 × 10⁵
n = 14.67
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The half-life of chromium-51 is 28 days. If a sample contained 510 grams, how much chromium would remain after 1 year?
Answer:
N = 365 / 28 = 13 half-lives in one year
(1/2)^13 = .000122 fraction remaining in one year
510 * .000122 = .062 grams
A horizontal line labeled B has an arrow labeled A strike it from right and above and then another arrow D emerges from the strike point at the same angle as A. A dotted line C evenly divides the angle between A and D.
In the mirror diagram shown, which is the normal?
A
B
C
D
Answer:
c is the actual answer.
Explanation:
Answer:
c is correct
Explanation:
At the gym, a man pulls a bar on a machine that works the muscles of the upper back. It takes him 0.5 seconds to raise 30 kilograms of weights a vertical distance of 0.5 meters. Which of these exerts the same power output? (Estimate g as 10 m/s2.)
A) lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds
B) lifting 45 kilograms a distance of 2.4 meters in 3.0 seconds
C) leg pressing 45 kilograms a distance of 0.5 meters in 0.5 seconds
D) bench pressing 30 kilograms a distance of 0.5 meter in 1.5 seconds
Answer: Lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds
Explanation:
Got it wrong and that’s the answer
Lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds exerts the same power output. Hence, option (A) is correct.
What is power?The quantity of energy moved or converted per unit of time is known as power in physics. The watt, or one joule per second, is the unit of power in the International System of Units.
Power is also referred to as activity in ancient writings. A scalar quantity is power.
Power required for lifting 30 kilograms of weights a vertical distance of 0.5 meters in 0.5 second = (30×9.8×0.5)/0.5 watt = 294 watt.
Power required for lifting 25 kilograms a distance of 2.4 meters in 2.0 seconds= (25×9.8×2.4)/2.0watt = 294 watt.
Power required for lifting 45 kilograms a distance of 2.4 meters in 3.0 seconds = (45×9.8×2.4)/3.0watt = 352.8 watt.
Power required for lifting 45 kilograms a distance of 0.5 meters in 0.5seconds = (45×9.8×0.5)/0.5watt = 441 watt.
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is elasticity a property of a sound wave
Answer:
Elasticity is involved whenever atoms vibrate, so yes it is an example of movement of a sound wave.
The sound wave travels more rapidly through the steel of the track than through the air, because the elastic modulus of steel is a million times greater than the bulk modulus of air.
Electromagnetic induction occurs when
a.
b.
a conductor is moved through a magnetic
a magnet is connected to an electrical circ
electrons are rubbed from one object onto
electrons flow from one chemical to anoth
C.
d.
your hd
Answer:
A
Explanation:
occurs when a magnetic feild and an elctric conductor move relative to one another
Imagine that you are observing the region of space where a cloud of gas and dust is beginning to collapse inward to form a star (the object that initially forms in this process is called a protostar). Will the atoms in the collapsing cloud move away from one another, move closer to one another, or stay at the same locations? 2) What physical interaction, or force, causes the atoms to behave as you described they would in Question 1?
Answer:
1. The atoms in the collapsing cloud would move closer to one another.
2. Gravity
Explanation:
1. This is because there is a force of attraction between the atoms of the collapsing cloud. Thus, the atoms in the collapsing cloud would move closer to one another.
2. This is because gravity is the force of attraction between masses. Now, the collapsing cloud of dust contains mass of atoms, and as the atoms come together due to gravity, they form a larger mass which develops into a star.
(a) The atoms in the collapsing cloud would move closer to one another.
(b) Due to the force of interaction between masses that is gravity
What is force of attraction?
(a) The atoms will come closer
This is because there is a force of attraction between the atoms of the collapsing cloud. Thus, the atoms in the collapsing cloud would move closer to one another.
(b) Due to the gravitational attraction
This is because gravity is the force of attraction between masses. Now, the collapsing cloud of dust contains mass of atoms, and as the atoms come together due to gravity, they form a larger mass which develops into a star.
Hence
(a) The atoms in the collapsing cloud would move closer to one another.
(b) Due to the force of interaction between masses that is gravity
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Q11. A person has a mass of 70 kg. What is this person's weight? What is the force that this person exerts onto the Earth? What is the Earth's acceleration because of this person?
Answer:
[tex]weight = mg \\ = 70 \times 10 \\ = 700 \: newtons[/tex]
[tex]force = 700 \: newtons[/tex]
[tex]force = mass \times acceleration \\ 700 = 70 \times a \\ a = 10 \: {ms}^{ - 2} [/tex]
Someone is whirling a hammer that has a mass of 8.5 kg in the air that is tied to a Chain 1.5 m long in a circle that makes 1 revolution in 2 seconds a. What is the centripetal acceleration f the hammer B what is the tension of the Chain
Question 9 (Worth 4 points)
(02.06 HC)
a. Create and describe a scenario in which the forces acting on an object are unbalanced. Explain how you know the forces are unbalanced.
b. For your scenario, explain how Newton's third law of motion describes the forces involved.
a. When a football is kicked and it moves from one location to another, it indicates that unbalanced troops are responding to it and b. If an object A applies a force to another object B, then the other object B.
Describe how the effects of balanced and unbalanced forces on motion:The equilibrium of the forces is disturbed when an object's motion changes. Forces with opposite directions and equal sizes are said to be balanced forces. Motion remains constant when the forces are equal. In one of your scenarios from the previous section, you used the same amount of force on an object but pushed or pulled it in the opposite direction.
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Find the location of the CM of a system of three particles arranged such that two of the particles with mass m are separated by distance I along the y-axis. The third mass 2m lies on the x-axis and is separated by a distance I from one of the masses.
Answer:
CM of a system ( 0.5l , 0.25l )
Explanation:
x = (m1.x1 +m2.x2 +m3.x3) / ( m1 + m2 +m3)
x = ( m x 0 + m x 0 + 2m x l ) / ( m+m+2m)
x = 2m x l / 4m
x = 0.5 l
y = (m1 x y1 +m2 x y2 +m3 x y3) / ( m1 + m2 +m3)
y = (m x 0) + m x l + 2m x 0 ) / ( m + m + 2m )
y = m x l / 4m
y = 0.25 l
Light of intensity I0 passes through 4 ideal polarizing sheets. Unpolarized light enters the 1st sheet that has a horizontal transmission axis. Light continues to the 2nd sheet that has its transmission axis at 23 degrees with respect to the 1st sheet, then to the 3rd sheet that has its transmission axis at 42 degrees with respect to the 1st sheet then to the 4th sheet that has its transmission axis at 14 degrees with respect to the 3d sheet. The intensity of the emerging light as percentage of I0 is close to:
Answer:
I₄ / Io = 0.388 = 38.8%
Explanation:
For this exercise we will analyze the effect of having two depolarizers with an annulus between them, this is described by Malus's law
I = Io cos² θ
where tea is the angle between the two polarizers.
For this case we must apply this law to each pair of polarizers.
The light that reaches the first polarizer is non-polarized light, therefore only the light that has polarization is transmitted in the direction of the depolarizer, which is horizontal.
I₁ = I₀ / 2
this intnesidad reaches the second polarizer that has an angle of 23º with respect to the first polarizer
I₂ = I₁ cos² 23
I₂ = I₀ / 2 0.847
This light reaches the third polarizer, which has an angle of 42º with respect to the first polarized one.
Let's find the angle with respect to the 2nd polarizer
θ = 42- 23
θ = 19º
we apply the law of Malus
I₃ = I₂2 cos 19
I₃ = I₀ 0.847 / 2 0.9455
I₃ = Io 0.4
This intensity of light reaches the fourth polarizer, with an angle of 14º with respect to the 3polarizer
I₄ = Io 0.4 cos 14
I₄ = Io 0.4 0.970
I₄ = Io 0.388
to give this result as a percentage
I₄ / Io = 0.388 = 38.8%
which of the following could be effectively used to reduce friction (a) water (b)petrol (c) kerosene (d) grease
Answer:
[tex]\huge\boxed{\mathfrak{\underline{Answer...}}} \\ \\ \huge\mathfrak\red{grease} \\ \\ \huge\mathfrak\purple{hope \: it \: helps}[/tex]
What is the efficiency of an engine that exhausts 440 J of heat to a cold reservoir and receives 570 J of heat from a hot reservoir? *
Answer:
Efficiency = 77%
Explanation:
Input energy = 570 J
Output energy = 440 J
To find the efficiency;
[tex] Efficiency = \frac {Out-put \; energy}{In-put \; energy} * 100 [/tex]
Substituting into the equation, we have;
[tex] Efficiency = \frac {440}{570} * 100 [/tex]
[tex] Efficiency = 0.7719 * 100 [/tex]
Efficiency = 77.19 ≈ 77%
Therefore, the efficiency of the engine is 77 percent.
Question 1 of 10 Which of the following statements are true of liquids? Check all that apply. A. The particles have more kinetic energy than those of gases O B. The particles can move past each other within a fixed volume. C. The particles are in a fixed location. 0 D. There are intermolecular forces between the atoms or molecules. SUE
Answer:
B. The particles can move past each other within a fixed volume.
D. There are intermolecular forces between the atoms or molecules.
Explanation:
Which of the following is NOT a scientific hypothesis?
A. Neon atoms emit red light.
B. There is an attractive force between the earth and moon.
C. Halle Berry is attractive.
D. Summer days are hottest
E. The sky is blue.
The following statement is not a scientific hypothesis:
C. Halle Berry is attractive.
A scientific hypothesis is a proposed explanation for an observation or pattern in nature that can be tested through further investigation and experimentation. It should be testable, falsifiable, and based on evidence.
Neon atoms emit red light. This is a scientific hypothesis that can be tested and confirmed by looking at the spectrum of light emitted by neon atoms.
B. There is an attractive force between the earth and moon. This is a scientific hypothesis that can be tested and confirmed by measuring the force of gravity between the earth and moon.
D. Summer days are the hottest of the year. This is a scientific hypothesis that can be tested and confirmed by collecting temperature data during the summer months.
E. The sky is blue. This is a scientific hypothesis that can be tested and confirmed by observing the sky under different atmospheric conditions.
The statement "Halle Berry is attractive" is a subjective opinion that cannot be tested or confirmed through scientific investigation, hence it is not a scientific hypothesis. Attractiveness, as a concept, can vary widely based on personal, cultural, and social factors.
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When a low-pressure gas of hydrogen atoms is placed in a tube and a large voltage is applied to the end of the tube, the alors will emit electromagnetic radiation and visible light can be observed. If this light passes through a diffraction grating, the resulting spectrum appears as a pattern of four isolated, sharp parallel lines, called spectral lines. Each spectral line corresponds lo one specific wavelength that is present in the light emitted by the source. Such a discrete spectrum is referred to as a line spectrum
By the early 19th century, it was found that discrete spectra were produced by every chemical element in its gaseous slale. Even though these spectra were found to share the common feature of appearing as a set of isolated lines, it was observed that each element produces its own unique pattern of lines. This indicated that the light emitted by each element contains a specific set of wavelengths that is characteristic of that element.
part A What is the wavelength of the line corresponding to n =4 in the Balmer series? Express your answer in nanometers to three significant figures.
Part B What is the wavelength of the line corresponding to t=5 in the Balmer series? Express your answer in nanometers to three significant figures.
Answer:
A) λ = 4.88 10² nm, B) λ = 4.08 10² nm
Explanation:
The spectrum of hydrogen is correctly explained by the Bohr model, where the energy of each level is
Eₙ = -13.606 /n² [eV]
the transition generally occurs from a given level to a lower state nf <no, so a transition is
ΔE = E_f -Eₙ = -13,606 ( [tex]\frac{1}{n_f^2} - \frac{1}{n_o^2}[/tex] )
to find the wavelength let's use the planck relation
ΔE = h f
the speed of light is
c = λ f
we substitute
ΔE = h c /λ
λ = [tex]\frac{h \ c}{ \Delta \lambda}[/tex]
let's apply this equation to our case
the Balmer series has as final state the level n_f = 2
A) initial state n₀ = 4, final state n_f = 2
ΔE = -13.606 ( [tex]\frac{1}{2^2} - \frac{1}{4^2}[/tex] )
ΔE = 2.55 eV
let's reduce to SI units
ΔE = 2.55 eV (1.6 10⁻¹⁹ J / 1 eV) = 4.08 10⁻¹⁹ J
we calculate
λ = 6.63 10⁻³⁴ 3 10⁸ / 4.08 10⁻¹⁹
λ = 4.875 10⁻⁻⁷ m
we reduce to nm
λ = 4.875 10⁻⁷ m (10⁹ nm / 1m)
λ = 487.5 nm
we reduce to three significant figures
λ = 4.88 10² nm
B) initial state n₀ = 5
ΔE = -13,606 ( [tex]\frac{1}{2^2} - \frac{1}{5^2}[/tex] )
ΔE = 2,857 eV
we repeat the process of the previous point
ΔE= 2,857 1.6 10⁺¹⁹ = 4.286 10⁻¹⁹J
we look for the wavelength
λ = 6.63 10⁻³⁴ 3 10⁸ / 4.88 10⁻¹⁹
λ = 4.0758 10⁻⁷ m
we reduce to nm
λ = 4.0758 10² nm
ignificant numbers
λ = 4.08 10² nm