Ask question

Ask question

All categories

4 years ago

11

Alternating-current systems of 50V to 1,000V that supply premises wiring systems shall be grounded where supplied by a three-pha

se, 4-wire delta-connected system in which the midpoint of one phase winding is used as a circuit conductor. True or false?

2 answers:

Alexxandr [17]4 years ago

6 0

Answer:

The answer is false

Explanation:

mylen [45]4 years ago

4 0

Answer:

True

Explanation: due to the high leg,

It has to be grounded in order to stabilize the high alternating current voltage providing an alternative route for current to flow into the ground. and also protect it from lightening and thunder.

You might be interested in

Which of the following is a harmful effect of oil spills? (A)Migration of large schools of fish (B)Changes in sea level (C)Plant

kotegsom [21]

C is your answer to the question

4 0

3 years ago

Read 2 more answers

Usually, when the temperture is increased l, what will happen to the ratevof dissolving?

pochemuha

<span>When temperature is increased, the rate of dissolving increases. The kinetic energy of the molecules of the solute and solvent molecules is high thereby increasing their contact. An example is mixing powdered sugar to the water. When you add water to the sugar, the dissolving process is slow. However, when you increase the temperature of the water by boiling it, the sugar dissolves immediately. </span>

3 0

3 years ago

Suppose a light source is emitting red light at a wavelength of 700 nm and another light source is emitting ultraviolet light at

klasskru [66]

Answer:

b) twice the energy of each photon of the red light.

Explanation:

$\lambda$ = Wavelength

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

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

Energy of a photon is given by

$E=h\nu\\\Rightarrow E=h\dfrac{c}{\lambda}$

Let $\lambda_1$ = 700 nm

$\lambda_2=350\\\Rightarrow \lambda_2=\dfrac{\lambda_1}{2}$

For red light

$E_1=\dfrac{hc}{\lambda_1}$

For UV light

$E_2=\dfrac{hc}{\dfrac{\lambda_1}{2}}$

Dividing the equations

$\dfrac{E_1}{E_2}=\dfrac{\dfrac{hc}{\lambda_1}}{\dfrac{hc}{\dfrac{\lambda_1}{2}}}\\\Rightarrow \dfrac{E_1}{E_2}=\dfrac{1}{2}\\\Rightarrow E_2=2E_1$

Hence, the answer is b) twice the energy of each photon of the red light.

7 0

3 years ago

Read 2 more answers

The origin of an x axis is placed at the center of a nonconducting solid sphere of radius R that carries a charge +qsphere distr

MA_775_DIABLO [31]

Answer:

$q=49Q/64$

and

$x =16R/15$

Explanation:

See attached figure.

$E_{Q}=$ E due to sphere

$E_{q}=$ E due to particule

$E_{total}=E_{Q}-E_{q}=0$ (1)

according to the law of gauss and superposition Law:

$E_{Q}=E_{1}+E_{2}=E_{2}$ ; electric field due to the small sphere with r1=R/4

$E_{Q}=kq_{2}/(r_{1}^{2})=$

$q_{2}=density*4/3*pi*r_{1}^{3}=Q/(4/3*pi*R^{3})*4/3*pi*r_{1}^{3}=Q*r_{1}^{3}/R^{3}$

then: $E_{Q}=kq_{2}/(r_{1}^{2})=k*Q*r_{1}^{3}/(R^{3}*r_{1}^{2}) = kQ/(4*R^{2})$ (2)

on the other hand, for the particule:

$E_{q}=kq/(r_{p}^{2})$

$r_{p}=2R-R/4=7R/4$ ⇒ $E_{q}=16kq/(49R^{2})$ (3)

We replace (2) y (3) in (1):

$E_{total}=E_{Q}-E_{q}=0=kQ/(4*R^{2}) - 49kq/(16R^{2})$

$q=49Q/64$

--------------------

if R<x<2R AND $E_{total}=E_{Q}-E_{q}=0$

$E_{total}=E_{Q}-E_{q}=0=kQ/(x^{2}) - kq/(2R-x^{2})$

remember that $q=49Q/64$

then:

$Q(2R-x^{2})=49/64*x^{2}$

solving:

$x_{1} =16R/15$

$x_{2} =16R$

but: R<x<2R

so : $x =16R/15$

7 0

3 years ago

When searching for your word processing file to finish writing your report, you should look for a file with which extension?

ryzh [129]

Answer:

doc

Explanation:

6 0

3 years ago