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
Temka [501]
3 years ago
7

Calculate the average drift speed of electrons traveling through a copper wire with a crosssectional area of 80 mm2 when carryin

g a current of 30 A (values similar to those for the electric wire to your study lamp). Assume one electron per atom of copper contributes to the current. The atomic mass of copper is 63.5 g/mol and its density is 8.93 g/cm3 . Avogadro’s number is 6.022 × 1023 and the fundamental charge is 1.602 × 10−19 C. Answer in units of m/s.
Physics
1 answer:
Vedmedyk [2.9K]3 years ago
6 0

Answer:

The correct answer is 2.8*10^{-5}ms^{-1}

Explanation:

The formula for the electron drift speed is given as follows,

u=I/nAq

where n is the number of of electrons per unit m³, q is the charge on an electron and A is the cross-sectional area of the copper wire and I is the current. We see that we already have A , q and I. The only thing left to calculate is the electron density n that is the number of electrons per unit volume.

Using the information provided in the question we can see that the number of moles of copper atoms in a cm³ of volume of the conductor is 8.93/63.5 molcm^{-3}. Converting this number to m³ using very elementary unit conversion we get 140384molm^{-3}. If we multiply this number by the Avagardo number which is the number of atoms per mol of any gas , we get the number of atoms per m³ which in this case is equal to the number of electron per m³ because one electron per atom of copper contribute to the current. So we get,

n=140384*6.02*10^{23} = 8.45*10^{28}electrons.m^{-3}

if we convert the area from mm³ to m³ we get A=80*10^{-6}m^{2}.So now that we have n, we plug in all the values of A ,I ,q and n into the main equation to obtain,

u=30/(8.45*10^{28}*80*10^{-6}*1.602*10^{-19})\\u=2.8*10^{-5}m.s^{-1}

which is our final answer.

You might be interested in
the atomic number of cesium (Cs) is 55. If an atom of cesium has 78 neutrons, what is the atomic mass of cesium?
Slav-nsk [51]
Atomic mass= number of protons + number of neutrons
55 + 78 = 133
hope this helps
7 0
2 years ago
Read 2 more answers
How do solar panels work with conduction, convection and radiation?
Lady_Fox [76]

Answer:

<em>In the case of a solar thermal panel we are trying to heat above the ambient temperature so conduction and convection will work against us by taking heat from the panel to the out- side world. ... The sun (at 6000 C surface temperature) is hotter than the solar panel so the panel will get hot due to the solar radiation.</em>

Explanation:

3 0
3 years ago
HELP URGENT!!!!!!!!!!!!!!!!!!!!!!!!
nirvana33 [79]
D
Because the rest of the answers are illogical
5 0
3 years ago
How is sunlight different from light produced by a light bulb or by a fluorescent light bulb
Leona [35]
Sunlight emits more energy than artificial light. Sunlight is better and healthier than most artificial lights and helps plants to grow more.
4 0
3 years ago
A mass m is tied to an ideal spring with force constant k and rests on a frictionless surface. The mass moves along the x axis.
7nadin3 [17]

Answer:x=\frac{x_m}{\sqrt{2}}

Explanation:

Given

initially mass is stretched to x_m

Let k be the spring Constant of spring

Therefore Total Mechanical Energy is \frac{kx_m^2}{2}

Position at which kinetic Energy is equal to Elastic Potential Energy

K=\frac{mv^2}{2}

U=\frac{kx^2}{2}

it is given

k=U

thus 2U=\frac{kx_m^2}{2}

2\times \frac{kx^2}{2}=\frac{kx_m^2}{2}

2x^2=x_m^2

x=\frac{x_m}{\sqrt{2}}

3 0
3 years ago
Other questions:
  • In gym class you run 22 m horizontally, then climb a rope vertically for 6.2 m. What is the direction angle of your total displa
    14·2 answers
  • When calculating power what two pieces of information are needed?
    5·1 answer
  • A cyclist is riding a bicycle at a speed of 22 mph on a horizontal road. The distance between the axles is 42 in., and the mass
    6·1 answer
  • A projectile is fired vertically upwards and reaches a height of 78.4 m. Find the velocity of projection and the time it takes t
    8·1 answer
  • Which statement about dwarf planet locations is correct?
    7·2 answers
  • Studies show that the amount of heat stored in the ocean is increasing. What effect might this have?
    12·2 answers
  • Where does crystallization take place?
    13·1 answer
  • What is antoine lavoisier conservation of mass equation
    15·1 answer
  • 1. Which of the following best describes a nebula?
    11·1 answer
  • Calculate the acceleration of a train travelling from rest to 24 m/s in 12 seconds.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!