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
What tells scientists about distant galaxies? a. How fast light travels c. The color of light that they give off b. If the are o
tamaranim1 [39]
I Believe the answer is A but D looks good too.
8 0
2 years ago
If the world population grows at a constant rate of 1.8% per annum, how many years will it take to double? A) 17.7 years
AleksandrR [38]

Answer:

after 38.8 years it will double

correct option is D 38.8 years

Explanation:

given data

population grows rate = 1.8%

to find out

how many years will it take to double

solution

we consider here initial population is x

so after 1 year population will be = (100% + 1.8% ) x = 1.018 x

and after n year population will be = 1.018^{n} x

so it will double

2x = 1.018^{n} x

take log both side

log 2 = n log (1.018)

n = \frac{log2}{log1.018}

n = 38.853

so after 38.8 years it will double

correct option is D 38.8 years

4 0
2 years ago
Consider two positively charged particles, one of charge q₀ (particle 0) fixed at the origin, and another of charge q₁ (particle
docker41 [41]

Answer:

Explanation: according to Coulomb's inverse-square law is proportional to the square of distance between them and is given by

F=k\frac{q_0q_1}{r^2}

where r is the distance between the charges & k is the Coulomb's constant

k=1/(4*ε_0*π)

k=9*10^9

the distance between the charges in this question is d_1

hence the magnitude of the force exerted by q_0 on q_1 is given by

F=k\frac{q_0q_1}{d_1^2}

due to location of particle 1 above the particle 0 the direction of force is parallel to y axis and in vector form

F=k\frac{q_0q_1}{d_1^2} j

4 0
3 years ago
Assuming things about someone based on your experiences with similar people you have encountered is called
AysviL [449]

Answer:

presumptuous

Explanation:

it's what you call someone who assumes something

3 0
3 years ago
A bag of sugar weighs 2 kg on earth. What should it weigh in newtons on the moon, where the free-fall acceleration is 1/6 that o
Elis [28]
<span> Weight = mass x acceleration
Earths acceleration is 9.8 m/s*2
1 kg = 2.2 lbs, so 2.0 lbs x 1 kg/2.2 lbs = 0.91 kg
The bag would have a weight of 9.8 x 0.91 = 8.9 N

1. 8.9 x 1/6 = 1.5 N

2. 8.9 x 2.64 = 23.5 N

The mass of the bag at all three locations is 0.91 kg. Mass does not change, the different locations only change its weight. </span>
5 0
3 years ago
Other questions:
  • Literally don't know how to do this.
    9·1 answer
  • While standing at the edge of the roof of a building, you throw a stone upward with an initial speed of 7.83 m/s. the stone subs
    11·2 answers
  • The index of refraction of a thin lens is 1.5. Its one surface is convex (radius of curvature 20 cm) and the other planar. Calcu
    15·1 answer
  • A bicyclist makes a trip that consists of three parts, each in the same direction (due north) along a straight road. During the
    10·1 answer
  • The most common example of a(n) ____ switched network is the conventional telephone system.
    13·1 answer
  • Which part of the iceberg displaces water equal in weight to the buoyant force
    6·2 answers
  • Which statement best explains why an object appears green in sunlight?
    15·2 answers
  • This distance from the Earth to the Sun given above is a standard for measuring other distances in the solar system and is calle
    6·1 answer
  • Which of the following is an example of a SOLUTION?
    5·1 answer
  • according to karl popper, a discipline that claims to be a science is really a pseudoscience like astrology if it:
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!