1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Marysya12 [62]
3 years ago
13

The maximum wavelength that an electromagnetic wave can have and still eject electrons from a metal surface is 459 nm. What is t

he work function W0 of this metal? Express your answer in electron volts.
Physics
1 answer:
spin [16.1K]3 years ago
4 0

Answer:

2.7067 eV

Explanation:

h = Planck's constant = 6.626\times 10^{-34}\ m^2kg/s

c = Speed of light = 3\times 10^8\ m/s

\lambda_0 = Threshold wavelength = 459 nm

Work function is given by

W_0=\frac{hc}{\lambda_0}\\\Rightarrow W_0=\frac{6.626\times 10^{-34}\times 3\times 10^8}{459\times 10^{-9}}\\\Rightarrow W_0=4.33072\times 10^{-19}\ J

Converting to eV

1\ J=\frac{1}{1.6\times 10^{-19}}\ eV

4.33072\times 10^{-19}\ J=4.33072\times 10^{-19}\times \frac{1}{1.6\times 10^{-19}}\ eV=2.7067\ eV

The work function W0 of this metal is 2.7067 eV

You might be interested in
Some superconductors are capable of carrying a very large quantity of current. If the measured current is 1.00 ´ 105 A, how many
Zielflug [23.3K]

Answer:

The 6.25 \times 10^{23} electrons are moving through the superconductor per second.

Explanation:

Given :

Current I = 1 \times 10^{5} A

Charge of electron e = 1.6 \times 10^{-19} C

Time t = 1 sec

From the formula of current,

Current is the number of charges flowing per unit time.

   I = \frac{ne}{t}

Where n = number of charges means in our case number of electrons

   n = \frac{It}{e}

   n = \frac{1 \times 10^{5} }{1.6 \times 10^{-19} }

   n = 6.25 \times 10^{23}

Therefore, 6.25 \times 10^{23} electrons are moving through the superconductor per second.

5 0
3 years ago
A small metal cube measures 2.5 cm on one side. The mass of the cube is 1129.56 g. What is the density of the cube?
attashe74 [19]

-- volume = (length)(width)(height)

-- Since the cube is a cube, its three dimensions are all the same number.

Volume = (2.5cm)(2.5cm)(2.5cm)

Volume = 15.625 cubic cm

-- density = (mass) / (volume)

Density = (1129.56g) / (15.625cm^3)

Density = 72.3 g/cm^3

(roughly 3.2 TIMES the density of the most dense naturally occurring substance on Earth)

8 0
3 years ago
Two students, Jenny and Cho, are investigating motion.
IgorLugansk [536]

Answer:

1: a measuring instruments the students should use for time is a stopwatch

2: a measuring instruments the students should use for distance is a measuring tape

Explanation:

pls mark brainliest

8 0
1 year ago
Even though you are getting closer to the sun as you ascend into the toposphere, why does the temperature drop?
pishuonlain [190]

Answer: The lower areas of the Atmosphere have a high temperature through the heats from the ground.

Explanation: High temperature experienced on the Earth surface is majorly caused by heats from the ground ( Earth crust).As a person ascend up to the Toposphere the temperature continues to reduce because because the heat from the ground is reduced as the heights increased.

It has been proven that as a person ascends into the Toposphere the amount of air and pressure reduces this will eventually lead to expansion of the gas particles which will then reduce the temperature.

4 0
3 years ago
Read 2 more answers
Two identical point charges are 3.00 cm apart. find the charge on each of them if the force or repulsion is 4.00 x 10^-7. (Use C
DanielleElmas [232]

Answer:

Charge on each is 2 x 10⁻¹⁰.

Explanation:

We know that Force between two point charges is given b the Coulomb's law as:

F = kq₁q₂/r^2

k = 9 x 10^9

r = 3.00 cm

= 0.03 m

q₁ = q₂

F = 4.00 x 10^-7

Rearranging the formula, we get:

F = k q²/r²

q² = Fr²/k

q² = 4 x 10⁻⁷ x 0.03²/(9x10⁹)

q² = 4 x 10⁻²⁰

q = 2 x 10⁻¹⁰

As there is force of repulsion between the charges, the charges must be both positive or both negative.

3 0
3 years ago
Other questions:
  • A hydraulic lift is made by sealing an ideal fluid inside a container with an input piston of cross-sectional area 0.004 m2 , an
    7·1 answer
  • Someone please help me!
    8·1 answer
  • Which of the following statements is correct regarding transformers?
    12·2 answers
  • The temperature in the upper atmosphere is -2°C, and the temperature on Earth’s surface is 5°C. Which type of weather is most li
    15·2 answers
  • You just calculated that the heat of fusion for chloromethane is 6400 J/mol. The heat of fusion for hydrogen is 120 J/mol. Which
    5·1 answer
  • Find the specific gravity of the rose quartz. Specific gravity = density of of water.
    13·1 answer
  • Which wave causes the medium to vibrate only in a direction parallel to the wave’s motion?
    15·2 answers
  • Kinematics
    6·1 answer
  • PLEASE HELP!!! GIVING BRAINLIEST!! ill also answer questions that you have posted if you answer this correctly!!!! (40pts)
    6·2 answers
  • Given a force of 90 N and a acceleration of 30 m/s/s, what is the object’s mass?
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!