what is the energy (in j) of a photon required to excite an electron from n = 2 to n = 8 in a he⁺ ion? submit an answer to three signficant figures.

Answers

Answer 1

Answer:

Approximately [tex]5.11 \times 10^{-19}\; {\rm J}[/tex].

Explanation:

Since the result needs to be accurate to three significant figures, keep at least four significant figures in the calculations.

Look up the Rydberg constant for hydrogen: [tex]R_{\text{H}} \approx 1.0968\times 10^{7}\; {\rm m^{-1}[/tex].

Look up the speed of light in vacuum: [tex]c \approx 2.9979 \times 10^{8}\; {\rm m \cdot s^{-1}}[/tex].

Look up Planck's constant: [tex]h \approx 6.6261 \times 10^{-34}\; {\rm J \cdot s}[/tex].

Apply the Rydberg formula to find the wavelength [tex]\lambda[/tex] (in vacuum) of the photon in question:

[tex]\begin{aligned}\frac{1}{\lambda} &= R_{\text{H}} \, \left(\frac{1}{{n_{1}}^{2}} - \frac{1}{{n_{2}}^{2}}\right)\end{aligned}[/tex].

The frequency of that photon would be:

[tex]\begin{aligned}f &= \frac{c}{\lambda}\end{aligned}[/tex].

Combine this expression with the Rydberg formula to find the frequency of this photon:

[tex]\begin{aligned}f &= \frac{c}{\lambda} \\ &= c\, \left(\frac{1}{\lambda}\right) \\ &= c\, \left(R_{\text{H}}\, \left(\frac{1}{{n_{1}}^{2}} - \frac{1}{{n_{2}}^{2}}\right)\right) \\ &\approx (2.9979 \times 10^{8}\; {\rm m \cdot s^{-1}}) \\ &\quad \times (1.0968 \times 10^{7}\; {\rm m^{-1}}) \times \left(\frac{1}{2^{2}} - \frac{1}{8^{2}}\right)\\ &\approx 7.7065 \times 10^{14}\; {\rm s^{-1}} \end{aligned}[/tex].

Apply the Einstein-Planck equation to find the energy of this photon:

[tex]\begin{aligned}E &= h\, f \\ &\approx (6.6261 \times 10^{-34}\; {\rm J \cdot s}) \times (7.7065 \times 10^{14}\; {\rm s^{-1}) \\ &\approx 5.11 \times 10^{-19}\; {\rm J}\end{aligned}[/tex].

(Rounded to three significant figures.)


Related Questions

Hi sweeties.. I want 5 solving questions about (Fluid Pressure and Temperature) and (Archimedes' Principle) may u help me?!​

Answers

Answer:

1) A 1L bottle, with a height of 30cm, full of water is emptied. The bottle is filled with oil (density = 920 kg/m^3). Calculate the change in pressure of the bottom of the first bottle. If you decide to put potatoes (assume its density is  1,8 kg/m^3), each one of a volume V = 10 cm^3, will they float?

2) The fusion temperature of the Nitrogen is -210°C and its boiling temperature is 77K. Calculate the difference between the fusion temperature and the boiling temperature.

whats 10x10 PLEASE I NEED THIS

Answers

10 x 10
= 100

Hope you find this helpful! for solving such a difficult equation :3

Brainliest and a like is much appreciated!

Answer:

100

Explanation:

Where is iron made?

need help

Answers

Answer:
Nature- Iron is found in the earths crust.
Other- Iron can be found made in China, Australia, Brazil, India, Russia and many more.
Hope this helps!

Answer:

Explanation:

Do you mean "made" as in the element itself, or "made" as it is extracted from the Earth and refined.

====

The elements originate in the stars.  The fusion reactions in Earth's sun fuse hydrogen and helium atoms to make elements, up to iron.  Larger stars and powerful explosions such as supernova create the larger elements.  Humans, with the use of particle accelerators make even larger elements, nearly all of which are unstable and decay rapidly into smaller elements.  But their creation does offer the perk of naming rights if you can prove it was created, and don't pick a clearly untenable name.

The Fe in stardust from the sun collects in clumps via gravitational forces and, via meteorites, is carried to Earth.  This is the major source for pure iron on the Earth.

Iron has chemical properties that lead to it reacting with other substances (e.g., oxygen) and then becoming concentrated in deposits as a variety of salts  in the Earth's crust, as a result of natural processes.  These deposits are mined and the rock is heated to separate and purify the iron metal.

Given that the mass of a liquid is 0.01kg and the volume of the liquid is 0.05m^3 . Calculate the density of the liquid

A) 2kg/m^3

B)0.2kg/m^3

C) 5kg/m^3

D) 0.5kg/m^3​

Answers

Answer:

B.

Explanation:

Density = mass / volume

= 0.01/0.05

= 0.2 kg/m^3.

why is water soaked cloth used on forehead during fever?please can you tell me answer​

Answers

Answer:

This is because the cloth soaked in water can absorb and evaporate the heat from your forehead.

Explanation:

This technique is used to cool down your fever, and to help you feel better.

what is the prmary source of energy inside of the earth

Answers

The correct answer is the energy of the sun
The primary source would be the sun

what has to increase in order for an object to accelerate?

Answers

Answer:

Answer: B. Explanation: For an object to accelerate the force on it must be increased. According to Newton's second law of motion.

Explanation:

I do Accelerate to good luck


An airplane initially travels at 12 m/s when passing the "acceleration line." The airplane then
accelerates to 9 m/s2 until reaching its take off velocity of 40.0 m/s. What is the displacement of
the plane during the acceleration?

Answers

The displacement of  the plane during the acceleration is equal to 80.89 meters.

Given the following data:

Initial velocity = 12 m/sFinal velocity = 40 m/sAcceleration = 9 [tex]m/s^2[/tex]

To determine the displacement of  the plane during the acceleration, we would use the third equation of motion;

[tex]V^2 = U^2 + 2aS[/tex]

Where:

V is the final speed.U is the initial speed.a is the acceleration.S is the displacement traveled.

Substituting the given parameters into the formula, we have;

[tex]40^2 =12^2 + 2(9)S\\\\1600=144+18S\\\\18S=1600-144\\\\18S=1456\\\\S=\frac{1456}{18}[/tex]

Displacement, S = 80.89 meters.

Read more: https://brainly.com/question/13086772

what are the three elements that can be used to make a magnet?

Answers

Answer:

Iron, cobalt, and nickel are the only three naturally occurring elements that are magnetic. 

Explanation:

hope it helps

correct me if I'm wrong thank you

brainliest please

Answer:

The three elements that can be used to make a magnet are :

Aluminum, nickel and cobalt

Student 1 lifts a box with a force of 500 N and sets it on a tabletop 1.2 m high. Student 2 pushes an identical box up a 5 m ramp from the floor to the top of the same table. Which student did the MOST work?

Answers

The student who did the most work is student 2 with 2500 Joules.

Given the following data:

Force 1 = 500 NewtonDistance 1 = 1.2 meterForce 2 = 500 NewtonDistance 2 = 5 meter

To determine which of the students did the most work:

Mathematically, the work done by an object is given by the formula;

[tex]Work\;done = Force \times distance[/tex]

For student 1:

[tex]Work\;done = 500 \times 1.2[/tex]

Work done = 600 Joules

For student 2:

[tex]Work\;done = 500 \times 5[/tex]

Work done = 2500 Joules.

Therefore, the student who did the most work is student 2 with 2500 Joules.

Read more: Read more: brainly.com/question/13818347

Answer:student 2 did the most work

Explanation:student 2 did more work because he pushed it up 5 m instead of 1.2.

What is the low end of the range of surface temperature for blue white stars

Answers

B 10,000 - 30,000 K Blue-white stars

A 7,500 - 10,000 K White stars

F 6,000 - 7,500 K Yellow-white stars

G 5,000 - 6,000 K Yellow stars (like the Sun)

The lowest temperature stars are red while the hottest stars are blue. Astronomers are able to measure the temperatures of the surfaces of stars by comparing their spectra to the spectrum of a black body.

Two students are sitting on a see-saw. The length of the board is 2 meters with the
pivot point being in the very center. One student sitting on the end of the left side
has a mass of 34 kg. If the student sitting on the right has a mass of 42.5 kg, where
should she sit for the see-saw to be in equilibrium?

Answers

To solve the problem it is necessary to apply the concepts of Torque and equilibrium.

The Torque is defined as:

Where

F= Force

d = Distance

In this particular case, the force is caused by the weight of both children.

In turn, when there is equilibrium, the two torques must be equal therefore

Replacing with our values

Re-arrange to find  

Therefore the distance that the second kid should sit to balance the see-saw is 1.8m from the pivot.

A roller coaster
produces acceleration due
to changes in both speed
and direction. Applying
Concepts Describe the
acceleration occuring at this
instant on the
rollercoaster ride.

Answers

Answer:

the answer is the rollar coster

Explanation:

because the rollar coster is

what is the meaning of " hi baby girl "

Answers

Explanation:

it's mean hI small little cute baby girl ...

How much power is used in question #2 if the power time was 100secs
I really need the Formula, substitute & solve , answer with units.

Answers

Answer:

I just put a random number for the work

Explanation:

I hope it is ok.

The Doppler technique for planet detection has found Earth-like planets around nearby Sun-like stars. (True or False) ____________________

Answers

Answer: false

Explanation:

can someone explain it with steps?

A car was moving on a road at a constant speed of 15 m/s when suddenly the car driver saw some animal on the road at a distance of 21 m from the car, so he applied the brakes after a response time of 0.4 s and stopped before hitting the animal by 1 m. What was the deceleration of the car?

a-7.5 m/s^2

b-5.2 m/s^2

c-8.0 m/s^2

d-5.6 m/s^2​

Answers

Answer:

Option C is the correct answer

Explanation:

Distance travelled by car during reaction time

[tex]=15\times0.4\\\\=6m[/tex]

The car stopped before hitting the animal by [tex]1 m[/tex]

Distance travelled during deceleration is [tex]21-6-1=14m[/tex]

Hence by [tex]v^2=u^2+2as[/tex]

We have

[tex]0^2=15^2+2 \cdot a \cdot 14\\\\a=\frac{-225}{28} \\\\=-8.03m/s^2[/tex]

Option C is the correct answer

Initial velocity=15m/s=uFinal velocity=0deacceleration=a

Distance traveled during reaction time

15(0.4)=6m

Total distance

21-6-1=14m

[tex]\\ \sf\longmapsto v^2-u^2=2as[/tex]

[tex]\\ \sf\longmapsto -(15)^2=2(14)a[/tex]

[tex]\\ \sf\longmapsto -225=28a[/tex]

[tex]\\ \sf\longmapsto a=-8.0m/s^2[/tex]

can someone explain please?​

Answers

Hi there!

We can begin by solving for the velocity in which the ball was thrown at using the following:

[tex]v_f^2 = v_i^2 + 2ad[/tex]

At the top of the trajectory, the ball's velocity is equal to 0 m/s, so:

[tex]0 = v_i^2 + 2ad\\\\vi^2 = 2ad \\\\[/tex]

'a' = acceleration due to gravity and 'd' is the max height, so:

[tex]v_i^2 = 2(10)(5)\\\\v_i^2 = 10 m/s[/tex]

Now, we can use the same equation to calculate the final speed at 4.5 m. Remember, the acceleration is NEGATIVE in this instance (taking the negative direction to be in the direction of gravity).

[tex]v_f^2 = 10^2 - 2(10)(4.5)[/tex]

[tex]v_f^2 = 10^2 - 2(10)(4.5)\\\\v_f^2 = 100 - 90 \\\\v_f^2 = 10 \\\\v_f = \boxed{3.1 m/s}[/tex]

Help it’s multiple choice 11 through 15 please!

Answers

1. • Here, force of gravity on the block = 20 N.

• Therefore, the normal force will also be the same, i.e., 20 N [According to Newton's Third Law, on every action, there is an equal and opposite reaction]

• The coefficient

[tex] u_{k} = 0.4[/tex]

• Force of friction =

[tex]u_{k} \times \: normal \: \: \: force \\ = 0.4 \times 20N \\ = 8N[/tex]

• Hence, the force of sliding friction between the block and the ground is 8 N.

• So, it is option c. 8 N

2. The answer is option d. continue in the same direction with no change in speed.

We know, force = mass × acceleration. When force is 0, then acceleration will also be 0 since mass cannot be 0. So, there will be no change in speed.

3. It is option b. force that is required to give a one kilogram object the acceleration of 1 m/s^2.

Newton is the SI unit of force. As mentioned earlier, force = mass × acceleration. The SI unit of mass and acceleration is Kg and m/s^2 respectively.

So, 1 N = 1 Kg × 1 m/s^2.

4. It is d. not zero.

Acceleration is the change in speed. So, if the force is zero, then acceleration will not occur.

5. Force = 2 N

Acceleration of the object A = 2 m/s^2.

Acceleration of the object B = 1 m/s^2.

Therefore, mass of the object A = 2 N ÷ 2 m/s^2 = 1 Kg

And, mass of the object B = 2 N ÷ 1 m/s^2 = 2 Kg

So, the mass of object B is greater than that of object A.

Hence, the answer is option c. Object B has more mass.

Hope you could get an idea from here.

Doubt clarification - use comment section.

the system shown above is released from rest. if friction is negligible, the acceleration of the 4.0 kg block sliding on the table shown above is most nearly

Answers

The acceleration of the first block (4 kg) is -9.8 m/s².

The given parameters:

Mass of the first block, m₁ = 4.0 kgMass of the second block, m₂ = 2.0 kg

The net force on the system of the two blocks is calculated as follows;

[tex]m_2 g - T = m_1 a[/tex]

where;

T is the tension in the connecting string due weight of the first block

[tex]m_2 g - m_1 g = m_1 a\\\\a = \frac{m_2 g - m_1g}{m_1} \\\\a = \frac{g(m_2 - m_1)}{m_1} \\\\a = \frac{9.8(2-4)}{2} \\\\a = -9.8 \ m/s^2[/tex]

Thus, the acceleration of the first block (4 kg) is -9.8 m/s².

Learn more about net force on two connected blocks here: https://brainly.com/question/13539944

if 9 joules of energy are expended pushing on one coulomb of charge round a circuit, what is the emf across the circuit?

Answers

W=9JQ=1C

[tex]\\ \sf\Rrightarrow V=\dfrac{W}{Q}[/tex]

[tex]\\ \sf\Rrightarrow V=\dfrac{9}{1}[/tex]

[tex]\\ \sf\Rrightarrow V=9V[/tex]

How much energy has 4x 1010 m³ of water collected in a reservoir at a 2. 3. height of 100 m from the power house? What kind of energy is that? (Given, mass of 1 m³ of water = 1000 kg)​

Answers

Explanation:

[tex] \rule{999pt}{66646pt}[/tex]

9. How are ecological footprints useful?

Answers


As ecological footprints provide an easily communicable way of measuring the ecological bottom‐line condition for sustainability, it is a useful tool for promoting a sustainable future. It is particularly useful for cities, as it is in cities where the battle for sustainability will be won or lost.

Answer:

This is what the Ecological Footprint does: It measures the biologically productive area needed to provide for everything that people demand from nature: fruits and vegetables, meat, fish, wood, cotton and other fibres, as well as absorption of carbon dioxide from fossil fuel burning and space for buildings and roads.

Why it's useful:

Ecological footprint (EF), measure of the demands made by a person or group of people on global natural resources. It has become one of the most widely used measures of humanity’s effect upon the environment and has been used to highlight both the apparent unsustainability of current practices and the inequalities in resource consumption between and within countries.

Why doesn't the skater ever regain his potential energy? ​

Answers

Answer:

Friction

Explanation:

As the skateboarder goes down the ramp, potential energy is converted to kinetic energy. Because of friction, some of the energy in the system is converted to heat energy. Once the kinetic energy is converted to heat, the energy cannot be converted back to the potential or kinetic energy in the system.

The mass of a sample of sodium bicarbonate is 2. 1 kilograms (kg). There are 1,000 grams (g) in 1 kg, and 1 Times. 109 nanograms (ng) in 1 g. What is the mass of this sample in ng? 2. 1 Times. 103 ng 2. 1 Times. 106 ng 2. 1 Times. 109 ng 2. 1 Times. 1012 ng.

Answers

2.1 kg of sodium bicarbonate is equal to the 2.1 x 10¹² ng of sample. Option D is correct.

Mass is the quantity of the substance in the body or object. The SI unit of mass is Kilogram.

There are other units of measure,

Milligram: 1 g is equal to the [tex]\bold {10^3 \ mg}[/tex]Micro-gram: 1 g is equal to [tex]\bold {10^{6} \ \mu g}[/tex]Nano-gram: 1 g is  is equal to[tex]\bold {10^{9} \ ng}[/tex]

First convert kg to gram,

Since, 1 Kg = 1000 g

2.1 kg = grams of sample

So,

Do the cross multiplication,

[tex]\rm mass\ of\ sample = \dfrac {2.1\ kg \times 1000\ g }{ 1 kg}\\\\\rm mass\ of\ sample =2100 g[/tex]

Now, convert 2100 g to nano-grams

Since, 1 g = 1 x 10⁹ ng

2100 g = ng of sample

So,

Do the cross multiplication,

[tex]\rm mass\ of\ sample = \dfrac {2100 g \times 1 \times 10^9 ng }{1\ g}\\\\\rm mass\ of\ sample = 2.1 \times 10^1^2 ng[/tex]

Therefore, 2.1 kg of  sodium bicarbonate is equal to the 2.1 x 10¹² ng of sample.

To know more about Mass units,

https://brainly.com/question/489186

what is the magnitude of the force exerted on the bottom of the bottle?

Answers

My answer is in the pic
Help me and mark as brainliest plz

1) A plane takes off from an O'Hare runway heading due west with a speed of 210.1 m/s. Once in the air, it encounters a north wind (blowing south) with a speed of 55.0 m/s. What is the magnitude of its velocity relative to the ground?

2) What is the direction of the resulting velocity (relative to its initial direction)?

Answers

I found this online Idek if it helps but First, determine how many degrees off the runway heading the reported wind is. So if you’re landing Runway 18 and the wind is 160 at 10, the wind is 20 degrees off the runway (180-160=20) . Now picture an analog clock face. How far is the wind angle number in minutes around the clock face? A wind angle of 20 degrees means 20 minutes around the clock face, which is one-third of the way around the clock face The crosswind component is one-third of the total wind. In this example, 10 knots * 1/3 = 3.3 knots of crosswind.

If you like charts, you can lay out common numbers and interpolate between them:

10-degree wind angle 10 minutes, which is 1/6 around clockface crosswind = 1/6 * total wind
15-degree wind angle 15 minutes, which is 1/4 around clockface crosswind = 1/4 * total wind
20-degree wind angle 20 minutes, which is 1/3 around clockface crosswind = 1/3 * total wind
30-degree wind angle 30 minutes, which is 1/2 around clockface crosswind = 1/2 * total wind
45-degree wind angle 45 minutes, which is 3/4 around clockface crosswind = 3/4 * total wind
60-degree wind angle or more 60 minutes, which is 100 percent of the way around a clockface crosswind component ≈ total wind speed

A race car makes one lap around a track of radius 180 m in 90.0 s. What is the centripetal acceleration in m/s2?
a
0.5
12.6
Ob
OC
Od
.87
2.
2

Answers

Answer:

0.9m/s^2 (yours is 0.87, so choose that)

Explanation:

formula for centripetal acceleration:

v^2/r

to find v, we know that f=1/90s, and r=180m.

v=(2pir)/T

v=(2pi(180))/90

v=12.6m/s

now plug into a=v^2/r

a=(12.6)^2/180

a=0.9m/s^2

A 6 kilogram block in outer space is moving at -100 m/s (to the left). It suddenly experiences three forces as shown below.

B) What equilibrant force is required to keep the block at rest once it does?


C) If you were to rearrange the three forces as you like, what maximum force could be applied to slow the block?


D) How much time would it take for the block to stop under maximum force conditions?

Answers

Newton's second law and the kinematic relations allow to find the results for the questions about forces and the movement of the block are:

    B) the force applied to maintain the system is equilibrium is: F = 0.39 N with an angle of tea = 180º

    C) The maximum force is: F = 24 N

    D) The time to stop the block is: t = 25 s

 

Newton's second law establishes a relationship between the net force, the mass, and the acceleration of the body. In the special case that the acceleration is zero it is called the equilibrium condition.

B) They indicate a diagram of forces on the block, let's look for the components of the force that the block maintains with zero acceleration, in the attached we have a free-body diagram including the force applied to keep the system in equilibrium.

x-axis

      -10 + 12 sin 60 + Fₓ = 0

        Fₓ = 10- 12 sin 60 = -0.39 N

y-axis

       12 cos 60 - 6 + F_y = 0

        F_y = 6 - 12 cos 60 = 0 N

We can give the result of the force in two ways:

Form of coordinates F = -0.39 i ^ N Form of module and angle.

Let's use Pythagoras' theorem to find the modulus.

       [tex]F = \sqrt{F_x^2 + F_y^2 } \\F = \sqrt{0.39^2 +0^2}[/tex]  

       F = 0.39N

We use trigonometry for the angle.

       [tex]tan \theta = \frac{F_y}{F_x}[/tex]

       tan θ=  0º

The component of the force is negative therefore this angle is in the second quadrant, to measure the angle from the positive side of the x axis in a counterclockwise direction.

        θ = 180 + θ'

        θ = 180 + 0

        θ = 180º

C) if the three forces can be moved and the maximum force occurs when they are all linear.

          10+ 6 + 6 + F = 0

          F = -24 N

D) if we maintain this force and eliminate the other three, the block stops, let's look for its acceleration.

          [tex]a = \frac{F}{m}[/tex]  

          a = [tex]\frac{24}{6}[/tex]  

         a =  4 m / s²

The acceleration is in the opposite direction of the initial velocity of the block v₀ = -100 m / s

If we use kinematic relations.

        v = v₀ - a t

Final velocity when stopped is zero

         t = [tex]\frac{0-v_o}{a}[/tex]

         t = 100/4

         t = 25 s

In conclusion using Newton's second law and the kinematics relations we can find the results for the questions about the forces and the motion of the block are:

    B) the force applied to maintain the system is equilibrium is: F = 0.39 N with an angle of tea = 180º

    C) The maximum force is: F = 24 N

    D) The time to stop the block is: t = 25 s

Learn more about Newton's second law here: brainly.com/question/25545050

NEED HELP ASAP PLEASE
The drop time can be calculated as follows t = sqrt((2y)/g) where y is the vertical height of the table and g is the acceleration due to gravity (9.80 m/)How did the calculated drop time compare to the average of your measured drop times? Find the percent error using the following equation measured drop time - calculated drop time % 100 calculated drop time What factors might cause the differences?

Answers

did you end up getting the answer- im struggling

Answer:

I would think human error could cause differences like not pressing the stop watch on time.

Explanation:

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Which of the following expressions is equivalent to. Please help me with this!!! I will mark brainlist!!! Directions: Name the coefficient (s) in the following expressions:1. 9s + 4t2. 46rs + 10x3. 18q + 14x4. 10x + 14y5. 17rs + 32x6. 5x + 7y - 5z7. 3ab + 70m8. 3r + 20a + 10m9. 7k + 16m10. 7r + 5s11. 9j + 120m12. 12k + m13. 6c + 15h + w14. 2c - 19d + 12f15. 3t + 14r - 31jcan someone just answer god Explain whether the pairing is a function 39 round to the nearest hundred What are the compounds that you can find in mayonnaise A solid object where the radius of bse is 7cm and height is 12cm Amare runs 1\10 mile in 2\3 minute. What is his speed in miles per minute? Show your work Find the slope of the line passing through the points A(-2,2) and B(7, -3) what is the meaning of enhanced Malcom and his sister ran 3 races. Their distances are shown below.Race Malcom's / Sister Distance 1. 10 yards 300 inches 2. 18 feet 180 inches 3. 120 inches 5 feet Who can run the farthest? How do you know? Use the lines and space below toprove your answer. What is Plumer's concern about a tie in the Electoral College? Why does he think this would be a bad outcome? Read this lines from Dream Variations by Langston Hughes Then rest at cool evening Beneath a tall tree While night comes on gently,Dark like me-what do these lines suggest?(Options in the pictures) I need help please is important :((( Can someone plz help me? :( 10/11 x 3/7 x 1/2 Multiply. Write your answer as a fraction in the simplest form. Identify an example of a pair of skew line from the box below At Christmas you re......gifts from your friends and family. what is the missing word? point mutations, such as silent, nonsense, and missense mutations, are caused by What is the length of CB in ABC