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
Virty [35]
3 years ago
13

A metallic wire has a diameter of 4.12mm. When the current in the wire is 8.00A, the drift velocity is 5.40×10−5m/s.What is the

density of free electrons in the metal?Express your answer numerically in m−3 to two significant figures.
Physics
2 answers:
podryga [215]3 years ago
3 0

Answer:

6.9\times 10^{28}m^{-3}

Explanation:

We are given that

Diameter of wire=d=4.12 mm

Radius of wire=rr=\frac{d}{2}=\frac{4.12}{2}=2.06mm=2.06\times 10^{-3} m

1mm=10^{-3} m

Current=I=8 A

Drift velocity=v_d=5.4\times 10^{-5} m/s

We have to find the density of free electrons in the metal

We know that

Density of electron=n=\frac{I}{v_deA}

Using the formula

Density of free electrons=\frac{8}{5.4\times 10^{-5}\times 1.6\times 10^{-19}\times 3.14\times (2.06\times 10^{-3})^2}

By using Area of wire=\pi r^2

\pi=3.14\\e=1.6\times 10^{-19} C

Density of free electrons=6.9\times 10^{28}m^{-3}

Furkat [3]3 years ago
3 0

Explanation:

We will calculate the density as follows.

               n = \frac{i}{v_{d}eA}

As the metallic wire is in the shape of a circle. So, its area will be calculated as follows.

                 Area = \pi \times r^{2}

                          = 3.14 \times (2.06 \times 10^{-3})^{2}

                v_{d} = 5.40 \times 10^{-5}

                        i = 8 A

Hence, we will calculate the density of free electrons as follows.

              n = \frac{i}{v_{d}eA}

                 = \frac{8}{5.40 \times 10^{-5} \times 3.14 \times (2.06 \times 10^{-3})^{2} \times 1.60 \times 10^{-19}}

                  = 6.950 \times 10^{28} m^{-3}

Thus, we can conclude that the density of free electrons in the metal is 6.950 \times 10^{28} m^{-3}.

You might be interested in
ben walks 2 m from his desk to the teachers desk. From the teachers desk he then walks 3 m in the same direction to the classroo
vaieri [72.5K]
Distance is the total length covered = 2m + 3m = 5m

Displacement is his distance from original position.

Displacement =  2m + (-3)m.               Representing the 3m walked back as -3.

Displacement = 2m - 3m = -1m.

So his displacement  is 1m behind his original starting point.
4 0
3 years ago
The universe could be considered an isolated system because
Stolb23 [73]

Answer:

A(many people think that no energy or matter exists outside the universe)

Explanation:

4 0
3 years ago
What is the photosynthes?
Westkost [7]
<em>It is the process in which green plants make their food through a green pigment known as Chlorophyll by using sunlight, Carbon-dioxide and water</em>.  <em>The result comes out with the formation of Oxygen as a byproduct. But in night they also respire like animals and photosynthesis does not occur. Photo means light and synthesis means manufacture.</em>
7 0
3 years ago
Read 2 more answers
Which of the following examples could this free body diagram describe? (Check all that apply)
boyakko [2]

Answer:

A car accelerating to the right

Explanation:

The free-body diagram shows all the forces acting on an object. The length of each arrow is proportional to the magnitude of the force represented by that arrow.

In this free-body diagram, we see that there are 4 forces acting on the object, in 4 different directions. We also see that the two vertical forces are equal so they are balanced, while the force to the rigth is larger than the force to the left: this means that there is a net force to the right, so the object is accelerating to the right.

Therefore, the correct answer is:

A car accelerating to the right

5 0
3 years ago
Question 8
Marrrta [24]

Answer:

It has a mass of 40 kg.

Explanation:

Because Force = mass x Acceleration or F = m a, we could say that the mass is force/acceleration which in your case is 2,400/60 which equals 40 kg.

3 0
2 years ago
Other questions:
  • Why is the work output of a machine never equal to the work input? A. Some work input is used to overcome friction. B. Input dis
    5·2 answers
  • Describe the results of Ernest Rutherford's gold-foil experiment and explain how his results changed ideas about the distributio
    13·1 answer
  • Which of the following is INCORRECT??
    6·2 answers
  • What is Acceleration?
    15·2 answers
  • A 1500 kg car drives around a flat, 50 m diameter track, starting from rest. The drive wheels supply a small but steady 525 N fo
    15·1 answer
  • a new car is advertised as having anti-noise technology. The manufacturer claims that inside the car any sound on negated. Evalu
    6·1 answer
  • Definition: The force applied when using a simple machine.
    7·2 answers
  • 3. An element that is malleable is
    10·2 answers
  • In a closed system, what happens to the total energy of the system as energy conversion takes place?
    9·1 answer
  • An engine develops 500 Nm of torque at 3900 rev/min. The power developed by the engine is ...
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!