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Marat540 [252]
3 years ago
15

Where conventional relays, contactors and switches, which have arcing contacts, are installed in Class I, Division 1 and 2 locat

ions, they must be enclosed in ? .
Physics
1 answer:
solmaris [256]3 years ago
7 0

Answer:

They must be enclosed in explosion proof housing or general-purpose housing (as per NEC Regulations)

Explanation:

It is important to know what are Class I, Division 1 and 2 locations.

Class I: includes those industries or places where flammable gases exists and there are chances of explosions.

Division 1: Those places where hazard can happen under normal operating conditions

Division 2: Those places where hazard can happen under abnormal conditions.

The conventional relays, contactors and switches cause arcing when they operate and this is a completely normal phenomenon but with respect to these categories, it is very dangerous to operate such electrical devices without any precaution.

Therefore industries are required by the regulatory authorities to install  explosion proof housing to enclose conventional relays, contactors and switches to avoid any explosion or hazard. General-purpose housing can also be used given that it follows the regulations provided by the NEC or any other regulatory authority.

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Can you access an instance variable from a static method? explain why or why not.
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Write down one fact about each of the following crust, mantle, outer, core, &amp; inner core
Oksanka [162]

Answer:

Hope this help you!!

Explanation:

Crust : The crust is the thinnest layer of the Earth. It has an average thickness of about 18 miles below land, and around 6 miles below the oceans. The crust is the layer that makes up the Earth's surface and it lies on top of a harder layer, called the mantle.

Mantle : The mantle is the mostly-solid bulk of Earth's interior. The mantle lies between Earth's dense, super-heated core and its thin outer layer, the crust. The mantle is about 1,802 miles thick, and makes up a whopping 84% of Earth's total volume

Outer Core : The outer core is the third layer of the Earth. It is the only liquid layer, and is mainly made up of the metals iron and nickel, as well as small amounts of other substances. The outer core is responsible for Earth's magnetic field. As Earth spins on its axis, the iron inside the liquid outer core moves around.

Inner Core : It's Almost The Size of the Moon. The Earth's inner core is surprisingly large, measuring 1,516 miles across. It's Mostly Made of Iron. It Spins Faster Than the Surface of the Earth. It Creates a Magnetic Field.

5 0
2 years ago
I need help with this please
Firdavs [7]
C is the answer to the question
6 0
3 years ago
Points a and b lie in a region where the y-component of the electric field is Ey=α+β/y2. The constants in this expression have t
Drupady [299]

Answer:

V_{a} - V_{b} = 89.3

Explanation:

The electric potential is defined by

         V_{b} - V_{a} = - ∫ E .ds

In this case the electric field is in the direction and the points (ds) are also in the direction and therefore the angle is zero and the scalar product is reduced to the algebraic product.

         V_{b} - V_{a} = - ∫ E ds

We substitute

         V_{b} - V_{a} = - ∫ (α + β/ y²) dy

We integrate

          V_{b} - V_{a} = - α y + β / y

We evaluate between the lower limit A  2 cm = 0.02 m and the upper limit B 3 cm = 0.03 m

           V_{b} - V_{a} = - α (0.03 - 0.02) + β (1 / 0.03 - 1 / 0.02)

            V_{b} - V_{a} = - 600 0.01 + 5 (-16.67) = -6 - 83.33

            V_{b} - V_{a} = - 89.3 V

As they ask us the reverse case

             V_{b} - V_{a} = - V_{b} - V_{a}

             V_{a} - V_{b} = 89.3

3 0
3 years ago
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