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
gladu [14]
3 years ago
15

. A current-carrying gold wire has diameter 0.87 mm. The electric field in the wire is 0.54 V>m. What are (a) the current car

ried by the wire; (b) the potential difference between two points in the wire 7.0 m apart; (c) the resistance of a 7.0-m length of this wire?
Physics
1 answer:
mixas84 [53]3 years ago
6 0

Answer:

a) I = 13.156 A

b) V = 3.78 V

c) R = 0.2873 Ω

Explanation:

The diameter(d) of the wire is 0.87 mm = 0.87 × 10⁻³ m.

The electric field(E) = 0.54 V/m

The cross sectional area(A) = πd²/4 = π × (0.87 × 10⁻³)² /4 = 5.945 × 10⁺⁷ m²

Gold resistivity(ρ) = 2.44 × 10⁻⁸

(a) the current carried by the wire

E = Jρ

Where J is the current density = I/A and I is the current

E = Iρ/A

I = EA/ρ

Substituting values:

I = 0.54 × 5.945 × 10⁺⁷/  2.44 × 10⁻⁸ = 13.156 A

(b) the potential difference between two points in the wire 7.0 m apart

The potential difference(V) = EL

Where L is the length = 7 m

V = EL

Substituting values:

V = 0.54 × 7 = 3.78 V

(c) the resistance of a 7.0-m length of this wire

The resistance(R) = ρL/A

R =  ρL/A

Substituting values:

R = 2.44 × 10⁻⁸ × 7 /  5.945 × 10⁺⁷ = 0.2873 Ω

You might be interested in
1) A thin ring made of uniformly charged insulating material has total charge Q and radius R. The ring is positioned along the x
allochka39001 [22]

Answer:

(A) considering the charge "q" evenly distributed, applying the technique of charge integration for finite charges, you obtain the expression for the potential along any point in the Z-axis:

V(z)=\frac{Q}{4\pi (\epsilon_{0}) \sqrt{R^{2} +z^{2}}  }

With (\epsilon_{0}) been the vacuum permittivity

(B) The expression for the magnitude of the E(z) electric field along the Z-axis is:

E(z)=\frac{QZ}{4\pi (\epsilon_{0}) (R^{2} +z^{2})^{\frac{3}{2} }    }

Explanation:

(A) Considering a uniform linear density λ_{0} on the ring, then:

dQ=\lambda dl (1)⇒Q=\lambda_{0} 2\pi R(2)⇒\lambda_{0}=\frac{Q}{2\pi R}(3)

Applying the technique of charge integration for finite charges:

V(z)= 4\pi (ε_{0})\int\limits^a_b {\frac{1}{ r'  }} \, dQ(4)

Been r' the distance between the charge and the observation point and a, b limits of integration of the charge. In this case a=2π and b=0.

Using cylindrical coordinates, the distance between a point of the Z-axis and a point of a ring with R radius is:

r'=\sqrt{R^{2} +Z^{2}}(5)

Using the expressions (1),(4) and (5) you obtain:

V(z)= 4\pi (\epsilon_{0})\int\limits^a_b {\frac{\lambda_{0}R}{ \sqrt{R^{2} +Z^{2}}  }} \, d\phi

Integrating results:

V(z)=\frac{Q}{4\pi (\epsilon_{0}) \sqrt{R^{2} +z^{2}}  }   (S_a)

(B) For the expression of the magnitude of the field E(z), is important to remember:

|E| =-\nabla V (6)

But in this case you only work in the z variable, soo the expression (6) can be rewritten as:

|E| =-\frac{dV(z)}{dz} (7)

Using expression (7) and (S_a), you get the expression of the magnitude of the field E(z):

E(z)=\frac{QZ}{4\pi (\epsilon_{0}) (R^{2} +z^{2})^{\frac{3}{2} }    } (S_b)

4 0
3 years ago
The method of heat transfer by which the sun energy reaches the earth is
aniked [119]

Answer:

C. Radiation

Explanation:

6 0
3 years ago
Why won't a chain reaction occur in natural uranium?
SOVA2 [1]
<span>The density of fissionable uranium is not high enough. Basically more neutrons are absorbed than are produced so any chain reaction dies. hope this helps</span>
5 0
3 years ago
PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!!<br><br> Which represents the smallest number?
Aleks04 [339]

c would be the correct answer because when its a negative power your moving the decimal to the left whic makes the number smaller

8 0
3 years ago
Read 2 more answers
An air-gap, parallel plate capacitor with area A and gap width d is connected to a battery that maintains the plates at potentia
sergejj [24]

Answer:

The new potential energy decreases by the factor of 2 to the old potential energy.

Explanation:

Capacitance of a parallel plate capacitor is given by the relation :

C = (ε₀A)/d

Here ε₀ is vacuum permittivity, A is area of the capacitor plate and d is the distance between them.

Potential energy of the capacitor, U = \frac{1}{2}CV^{2}

Here V is the potential difference between the plates.

According to the problem, the distance between the plates get double but area remains same. So,

d₁ = 2d

Here d₁ is new distance between the plates.

Hence, new capacitance is :

C₁ = (ε₀A)/d₁ = (ε₀A)/2d = C/2

The capacitor have same potential difference that is V. Hence, the new potential energy is :

U₁ = \frac{1}{2}C_{1} V^{2} = \frac{1}{2}\frac{C}{2} V^{2}

U₁ = U/2

\frac{U_{1} }{U} = \frac{1}{2}

7 0
3 years ago
Other questions:
  • "A student bikes to school by traveling first dN = 0.900" and "Similarly, let d⃗ W be the displacement vector corresponding to t
    15·1 answer
  • Not sure on this I know it’s not D please help
    7·1 answer
  • A red cart has a mass of 4 kg and a velocity of 5 m/s. There is a 2-kg blue cart that is parked and not moving, thus its velocit
    10·1 answer
  • What must a scientist do in order to develop a testable hypothesis?
    7·2 answers
  • Why is area called scalar quantity​
    15·1 answer
  • Please help<br>What is the angle of the reflected ray in the diagram above?​
    11·1 answer
  • Does anyone know how to solve series parallel and combo circuits
    8·1 answer
  • The data table for the decomposition reaction of hydrogen peroxide H2 O2 shows how the reaction rate changes over time which sta
    15·2 answers
  • A car travels 100 km to the east. If the first half of the distance is driven at 50 km/h and the second half at 100 km/h, what i
    6·1 answer
  • 3. How do you record your score in the 3-Minute Step Test? A record the 60-second heart rate before activity B. record the 30-se
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!