When a certain metal is illuminated with light of frequency 2.9 ✕ 1015 Hz, a stopping potential of 7.0 V is required to stop the most energetic ejected electrons. What is the work function of this metal?

Answers

Answer 1

Answer:

4.96 eV

Explanation:

Recall the Einstein photoeletric equation;

KE = E - Wo

Where;

KE = kinetic energy of the ejected photoelectron

E= energy of the incident photon

Wo = Work function

But

KE = eV= 1.6 * 10^-19 C * 7 V /1.6 * 10^-19 C = 7 eV

E = hf/e = 6.6 * 10^-34 * 2.9 ✕ 10^15 Hz/1.6 * 10^-19

E = 11.96 eV

Hence;

Wo = E - KE

Wo = 11.96 eV - 7eV

Wo = 4.96 eV


Related Questions

6. Which of the following statements is true for displacement ?

a. It cannot be zero

b. Its magnitude is more than the distance covered by the object.​

Answers

Both are false..........

Science Check: Light Waves and Their Behavior 4 of 104 of 10 Items Question POSSIBLE POINTS: 1 Why is a light wave not considered a matter wave? A light wave is visible to humans. A light wave is visible to humans. A light wave moves faster than most waves. A light wave moves faster than most waves. A light wave does not have a wave length. A light wave does not have a wave length. A light wave travels through the vacuum of space. A light wave travels through the vacuum of space.

Answers

Answer:

A light wave travels through the vacuum of space

Explanation:

A light wave cannot be a matter wave because a matter wave is made up of

atoms while light wave is a form of radiation (electromagnetic). A matter wave requires a medium to travel while a light wave do not require medium to travel. Since light wave is a form of radiation, light can travel in vacuum.

Hence, the correct answer is A light wave travels through the vacuum of space

Complete the simulation for three different trails. Complete chart below, using the data for your simulation from each trail.

Answers

where’s the chart for the question?

Answer:

Are similar in pattern

Explanation:

edge 2021

Para fabricar la bicicleta de un niño pequeño se tiene en cuenta que la fuerza que puede desarrollar es menor que la de un adulto y que no sabe cambiar de desarrollo. Por ello, se fabrica con un solo plato y un solo piñón de desarrollo muy pequeño. El plato es de 28 dientes y el radio de la rueda mide 20 cm. Si queremos que el desarrollo sea de 1,4 calcula: - El número de dientes que debe tener el piñón de la bicicleta. - Cuántos metros avanza la bicicleta por cada pedalada completa.

Answers

Answer:

a) El piñón debe tener 20 dientes.

b) La bicicleta avanza aproximadamente 1,759 metros por cada pedaleada completa.

Explanation:

a) El plato es el engranaje más grande que forma parte del sistema de transmisión, acompañando a la cadena y el piñón integrado a la rueda trasera. Asumiendo que no existen pérdidas por fricción seca y que las condiciones de lubricación del sistema de transmisión son óptimas tal que las pérdidas de potencia son despreciables. Además, supongamos que la bicicleta viaja a velocidad constante, entonces tenemos la siguiente identidad mediante las definiciones de trabajo y potencia:

[tex]T_{P}\cdot \omega_{P} = T_{p}\cdot \omega_{p}[/tex] (1)

Donde:

[tex]T_{P}[/tex] - Torque del plato, en newton-metros.

[tex]T_{p}[/tex] - Torque del piñón, en newton-metros.

[tex]\omega_{p}[/tex] - Rapidez angular del piñón, en radianes por segundo.

[tex]\omega_{P}[/tex] - Rapidez angular del plato, en radianes por segundo.

Sabiendo el hecho que tanto el plato y el piñón experimenta la misma velocidad tangencial, podemos simplificar (1) como sigue:

[tex]\frac{T_{P}}{R_{P}} = \frac{T_{p}}{R_{p}}[/tex] (1b)

Puesto que el radio de cada elemento y el número de dientes son, por separado, directamente proporcionales al número de dientes, modificamos (1b) así y tenemos la siguiente identidad, la cual equivale a su vez a la razón de desarrollo:

[tex]\frac{T_{P}}{T_{p}} = \frac{N_{P}}{N_{p}} = \frac{R_{P}}{R_{p}} = \frac{\omega_{p}}{\omega_{P}}[/tex] (1c)

Donde:

[tex]N_{p}[/tex] - Número de dientes del piñón, sin unidad.

[tex]N_{P}[/tex] - Número de dientes del plato, sin unidad.

Si tenemos que [tex]r = 1,4[/tex] y [tex]N_{P} = 28[/tex], entonces tenemos que el número de dientes del piñón es:

[tex]r = \frac{N_{P}}{N_{p}}[/tex]

[tex]N_{p} = \frac{N_{P}}{r}[/tex]

[tex]N_{p} = \frac{28}{1,4}[/tex]

[tex]N_{p} = 20[/tex]

El piñón debe tener 20 dientes.

b) De acuerdo con la relación de desarrollo, por cada revolución realizada por el plato, el piñón realiza 1,4 revoluciones. Entonces, el avance realizado por la rueda trasera ([tex]s[/tex]), en metros, es igual al productor de la relación de desarrollo y la circunferencia de la rueda, es decir:

[tex]s = r\cdot 2\pi\cdot R[/tex] (1)

Donde [tex]R[/tex] es el radio de la rueda trasera, en metros.

Si conocemos que [tex]r = 1,4[/tex] y [tex]R = 0,2\,m[/tex], entonces el avance realizado por la rueda trasera es:

[tex]s = r\cdot 2\pi\cdot R[/tex]

[tex]s = (1,4)\cdot (2\pi)\cdot (0,2\,m)[/tex]

[tex]s \approx 1,759 \,m[/tex]

La bicicleta avanza aproximadamente 1,759 metros por cada pedaleada completa.

Which material is colder in a room where all the objects are in for a long time?
A. all objects are the same temperature
B. wooden desk
C. a metal chair
D. a smart board

Answers

Wooden desk it doesn’t conduct or absorb heat as much as metal or plastic

NEED HELP What is the energy transformation process when using a battery powered flashlight?Single choice.
(2 Points)

Electrical-electromagnetic-thermal

Electrical -light-thermal

Chemical-electrical-thermal-light

Chemical-thermal-light

Answers

Answer:

Chemical-thermal-lightChemical-electrical-thermal-light

hope it is helpful to you

A skydiver jumps from a stationary helicopter and reaches a steady vertical speed. She then opens her parachute. Which statement about the falling skydiver is correct?

A As her parachute opens, her acceleration is upwards.
B As she falls at a steady speed with her parachute open, her weight is zero.
C When she accelerates, the resultant force on her is zero.
alda
D When she falls at a steady speed, air resistance is zero.

Answers

Answer:

A) As her parachute opens, her acceleration is upwards.

Explanation:

The acceleration is the rate of change of the velocity.

Thus, if you have positive velocity and positive acceleration, your velocity increases

If you have positive velocity and negative acceleration, then your velocity decreases.

(The opposite happens when you have negative velocity).

Now, when the skydiver is falling, her velocity is downwards.

When she opens her parachute, her velocity downwards decreases.

This means that when she opens her parachute, she will have an acceleration in the opposite direction to her velocity, then at this point her acceleration is upwards.

We can conclude that the correct option is:

A) As her parachute opens, her acceleration is upwards.

What is the baseball's mechanical energy when it is at a height of 8.0 m? Explain.

Answers

Answer:

In this section, we elaborate and extend the result we derived in Potential Energy of a System, where we re-wrote the work-energy theorem in terms of the change in the kinetic and potential energies of a particle. This will lead us to a discussion of the important principle of the conservation of mechanical energy. As you continue to examine other topics in physics, in later chapters of this book, you will see how this conservation law is generalized to encompass other types of energy and energy transfers. The last section of this chapter provides a preview.

The terms ‘conserved quantity’ and ‘conservation law’ have specific, scientific meanings in physics, which are different from the everyday meanings associated with the use of these words. (The same comment is also true about the scientific and everyday uses of the word ‘work.’) In everyday usage, you could conserve water by not using it, or by using less of it, or by re-using it. Water is composed of molecules consisting of two atoms of hydrogen and one of oxygen. Bring these atoms together to form a molecule and you create water; dissociate the atoms in such a molecule and you destroy water. However, in scientific usage, a conserved quantity for a system stays constant, changes by a definite amount that is transferred to other systems, and/or is converted into other forms of that quantity. A conserved quantity, in the scientific sense, can be transformed, but not strictly created or destroyed. Thus, there is no physical law of conservation of water.

Systems with a Single Particle or Object

We first consider a system with a single particle or object. Returning to our development of (Figure), recall that we first separated all the forces acting on a particle into conservative and non-conservative types, and wrote the work done by each type of force as a separate term in the work-energy theorem. We then replaced the work done by the conservative forces by the change in the potential energy of the particle, combining it with the change in the particle’s kinetic energy to get (Figure). Now, we write this equation without the middle step and define the sum of the kinetic and potential energies, K+U=E; to be the mechanical energy of the particle

As the period of a wave increases, the frequency increases.
Please select the best answer from the choices provided
T/F

Answers

See the picture below

endjdjdjdjdjr

hshdhdhdhdh

whdhdhdhdj

shdhdhdhjd

dbdhdhdhdh

rjrjdjrjjdjr

dbdjdjdjdjd

ndjdjdhdhd

All mutations are favorable and increase the ability for the
organism's offspring to survive.
TRUE
FALSE

Answers

false sometimes you get a bad mutation

Please please help me :)

Answers

Answer:

Explanation:

2) From F=ma

Force =15×40=600N or kgm/s2

3)From the same equation making acceleration the subject of the formula will give

a=f÷m

=24÷4=6m/s2

4)m=f÷a

=45÷15=3kg

This graph shows how the reaction rate of a chemical reaction changed as concentration of reactant changed. Which sentence best describes how the reaction rate changed.​

Answers

Answer:

A

Explanation:

The Reaction rate is going down which is why its at 0 And the concetration line is going up which means increasing,

How do the nuclei of covalently bonded atoms help keep the bond together?

Neutral particles in the nucleus provide enough mass that the force of gravity holds the atoms together.
Neutral particles in the nucleus can become positive or negative in order to balance the charges.
Positive particles in the nucleus change into negative particles that enter electron shells.
Positive particles in the nucleus are attracted to shared electrons, so the atoms stay close together.

Answers

Answer: D.

Explanation:

Answer: The answer is D

Explanation: I got it right on my test

As global population ______
a.) increases b.) decreases
food production must _____
a.) increase b.) decrease ​

Answers

Answer:

As global population a.) increases food production must a.) increase.

Example:

More people means more food must be produced.

Which geologic events occur most often at this mid-oceanic ridge plate

boundary? *

2 points

Mid-oceanic ridge

plate boundary

Shelf

Sea level

Patella

Plate 2

Continental

crust

Rigid mantle

Asthenosphere

magnetic pole reversals and cooling of ocean water

hydrospheric pollution and adiabatic heating

earthquakes and volcanic eruptions

Answers

Answer: Earthquakes and Volcanic eruptions

Explanation:

You did not attach a picture however, this should be the correct answer.

Mid-oceanic ridge plate  boundaries such as the Mid-Atlantic Ridge form as a result of plate separating at the boundary. This leads to earthquakes due to the forces of tension acting on the plates.

When this happens, the mantle is exposed and therefore there will be volcanic eruptions as the lava comes to the surface as magma. When this magma cools it creates new seafloors and underwater mountains.

what does the slope of a velocity-time graph reveal about an objects motion

Answers

Answer:

The slope of a velocity graph represents the acceleration of the object. So, the value of the slope at a particular time represents the acceleration of the object at that instant.

Answer:

The slope of a velocity graph represents the acceleration of the object.

Explanation:

So, the value of the slope at a particular time represents the acceleration of the object at that instant.

-1
9
5 points
An engine does 1421000 J of work to lift a beam 145 meters. How much force was exerted to lift the beam.
1566N
9800N
20445 N
50000N

Answers

Answer:

9800 N

Explanation:

applying,

W = Fd.................. Equation 1

Where W = work done by the engine, F = Force exterted to lift the beam, d = distance.

make F the subject of the equation

F = W/d............... Equation 2

From the question,

Given: W = 1421000 J, d = 145 meters.

Substitute these values into equation 2

F = 1421000/145

F = 9800 N

Sound waves are blank waves

A) Longitudinal
B) mechanical
C) compression
D) all if the above

Answers

B.) Mechanical

Reason: These particle-to-particle, mechanical vibrations of sound conductance qualify sound waves as mechanical waves. Sound energy, or energy associated with the vibrations created by a vibrating source, requires a medium to travel, which makes sound energy a mechanical wave
i’m pretty sure the correct answer is D)

Amos runs up a flight of stairs with a. total change in energy E. Vanessa exerts double the amount of energy in twice the time. How does Amos power output, Pa compare with Vanessa's power output, Pv?

Answers

Answer: Pa=Pv

Explanation:

Khan academy

Amos runs up a flight of stairs with a total change in energy ΔEA. Vanessa exerts double the amount of energy in twice the time.

How does Amos’s power output, PA, compare with Vanessa’s power output, Pv?

Answer: Pa=Pv

A train was moving at 50m/s and slow down to 20 m/s in 50 seconds, what was its acceleration?

Answers

Answer:

-0.6 m/s^2

Explanation:

a = change in velocity / time

change in velocity = 50 m/s - 20 m/s = 30 m/s

time = 50 s

30 m/s / 50s

= 0.6 m/s^2

because it is decelarating, it will be -0.6 m/s^2

Which explanation describes why a balloon will stick to a wall?
Opposites attract.
Like repels like.

Answers

Opposites attract is the answer

Answer: A is the correct answer :)

Explanation:

Question 2 (5 points)
(04.02 LC)
Which of the following energy conversions takes place in plants during photosynthesis? (5 points)
a
Chemical energy to light energy
b
Light energy to electrical energy
Ο Ο Ο
Electrical energy to light energy
Light energy to chemical energy

Answers

Answer:

Fossil fuels store energy from the sun as

Answer:

light to chemichal

Explanation:

Which of the following is an example of uniform circular motion?
A. Swinging on a swing
B. Spinning on a merry-go-round
C. Sliding down a slide
D. Bouncing on a trampoline

Answers

Answer:

B

Explanation:

First narrow answers to CIRCULAR motion.

Only A and B have circular motion.

Second look at the keyword UNIFORM. A swing does not have uniform motion because it will accelerate due to gravity and have the most velocity at the bottom of the swing.

Therefore, it must be B.

Answer: B

Explanation: uniform circular motion only occurs on a merry go round

Define Acceleration.
Ty!​

Answers

Answer:

Acceleration is the name we give to any process where the velocity changes. Since velocity is a speed and a direction, there are only two ways for you to accelerate: change your speed or change your direction—or change both.

Genes consist of portions of ______.

Answers

Answer: Genes consist of portions of proteins

wait how does this work hehe this is kinda fun lol yay

Answers

It’s pretty fun I guess ‍♀️ just trying to get points for school lol

What is the power of a hair dryer with a current of 4 A and a resistance of 60 ohms?

Answers

Answer:

960W

Explanation:

v=R×I

v=60ohm.4A=240v

p=VI

p=240v.4A

p=960W

The power of a hair dryer with a current of 4 A and a resistance of 60 ohms is 960 W.

What is power?

The amount of work completed in a given amount of time. Watt (W), which is derived from joules per second (J/s), is the SI unit of power. Horsepower (hp), which is roughly equivalent to 745.7 watts, is a unit of measurement sometimes used to describe the power of motor vehicles and other devices.

Given in the question a hair dryer with a current of 4 A and a resistance of 60 ohms power, p

Voltage, v=R×I

v=60 ohm.4 A=240 v

power, p=VI

p=240 v.4 A

p=960 W

The power of a hair dryer with a current of 4 A and a resistance of 60 ohms is 960 W.

To learn more about power refer to the link:

brainly.com/question/2289248

 #SPJ2

Question 4
The diagram represents the motion of a sound wave. The distance between points A and C is 9 meters (m), and it initially takes the wave 3 seconds (s) to travel.
What will be the wavelength of the sound wave if the velocity of the wave remains constant but the pitch is tripled?

A 3 meters
B 6 meters
с 9 meters
D 18 meters

Answers

Answer:A

Explanation:

The wavelength of the sound wave will be 3 meters.

What is wavelength?

The wavelength of any wave is defined as the distance between two max adjacent amplitudes, or the distance between two successive troughs or crest.

Now it is given that:

Distance =9 meters

time = 3 seconds

pitch=1/3 seconds

The velocity of  the sound will be

[tex]V=\dfrac{d}{t}=\dfrac{9}{3}=3\ \frac{m}{s}[/tex]

Now from the question the wavelength of the sound wave if the velocity of the wave remains constant but the pitch is tripled

so  [tex]f=3\times \dfrac{1}{3}=1 herts[/tex]

Now the velocity of the sound will be

[tex]v=f\times \lambda[/tex]

[tex]\lambda=\dfrac{v}{f}=\dfrac{3}{1}=3\ m[/tex]

Thus the wavelength of the sound wave will be 3 meters.

To know more about wavelength, follow

https://brainly.com/question/10728818

Which of the following is TRUE about thermal equilibrium?

Answers

Answer:

option one

Explanation:

equilibrium is used to describe the point in which something meets in this case the temperature of an object

Starting circuit One battery. 2 light bulbs in parallel; switch What is the voltage across the battery? What is the voltage across light bulb 1? What is the voltage across light bulb 2?​

Answers

Answer:

The voltage across light bulb 1 and light bulb 2 is the the same i.e V

Explanation:

In a parallel circuit, the Voltage is same across all the components of the circuit and the current flowing through each component is added to get the total current across the circuit.

Let us say, the voltage across the circuit is V. The voltage across light bulb 1 and light bulb 2 is the the same i.e V

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On January 1, 2018, UML Company leased a machine to UMB Corporation. The lease qualifies as a sales-type lease. UML paid $240,000 for the machine and is leasing it to UMB for $34,000 per year, an amount that will return 10% to UML. The present value of the lease payments is $240,000. The lease payments are due each December 31, beginning in 2018. What is the appropriate interest entry of UML on December 31, 2018 2. This is a group of lines in a poem, separaled by space from other groups of lines. It is like a paragraph. A central contrast presented in the passage is that between anticipated and actual instances of language change Answer A: anticipated and actual instances of language change A random and novel ways of directing future language changes Answer B: random and novel ways of directing future language changes B philosophical and psychological analyses of language use Answer C: philosophical and psychological analyses of language use C parochial and international approaches to changes in various languages Answer D: parochial and international approaches to changes in various languages D immediate and long-term views of language changes the ratio of the measure of the three angles in a trinagle is 10:3:7. Find the measure of the largest angle Anybody know this. Kinda need help if the sum of x and 3 is ten ,what is the value of x Return to DashboardASSIGNMENT LISTINFO00408-411Vocabulary ListGrammar ExplanationAnuncios due May 11th 11:59 PMEscribe los anuncios con la informacin dada. Usa la pasiva con se y el se impersonal y haz los cambios que sean necesarios.Modelo organizar una rifa i comprar computadoras / laboratorioSe organiza una rifa para comprar computadoras para el laboratorio.1. prohibir y no participar / los torneos deportivos de la escuela2. pedir participacin / elecciones para presidente estudiantil / proximo 30 de noviembre3. proponer / una iniciativa / reciclar basura en el barrio de la escuela4. poder / asistir / reuniones del centro estudiantil / todos los viernes5. buscar / voluntarios / acto de fin de curso Help please!!!list the physical factors that differentiate aquatic ecosystems.Question is from stemscopes Express (x 7)2 as a trinomial standard form Flora y fauna y en clima frio?? Please help me I ask you I am very stressed Which is the equation of the line that is parallel to the graph of y = 5x + 7 and has a y-intercept at -2? Which was not one of the major cause of he Cold War? 2 - 5 put explanation Can anybody help meh :(A total charge of 9.0 mC passes through a cross-sectional area of a nichrome wire in 3.6s. The number of electrons passing through the cross-sectional area in 10s is What is the answer to number 2?? in your answer in number 4 what was your understand?did you give reason/s on your stand ..im sorry po pangit lng talaga ung sulat ko btw i put brainless if tama po ung sagot The world population was 6.114 billion in 2000 with an estimated growthrate of 1.9% per year. Assuming the world population follows this exponentialgrowth mode, find the projected population in 2030. Which of the following is the term for a device (usually external to a computer) that is plugged into a computer's communicationport or connected wirelessly?An attachmentA peripheralA flash driveA plug-in In the marine carbon cycle, name the 3 processes that take place.