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4 years ago

What is the name that is used to reference the central primary cable distribution point in a building?

1 answer:

5 0

In telecomunications, the name MDF is used to designate the central primary distritution point in a building.

MDF stands for Main Distribution Frame.

It is a kind of rax where the signal from the phone company is distributed to the different cables that go to every apartment of the building.

Answer: MDF

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How do you change the currents in a circuit

mel-nik [20]

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Eddy Current Testing

Introduction
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Current Flow and Ohm's Law

Ohm's law is the most important, basic law of electricity. It defines the relationship between the three fundamental electrical quantities: current, voltage, and resistance. When a voltage is applied to a circuit containing only resistive elements (i.e. no coils), current flows according to Ohm's Law, which is shown below.

I = V / R

Where:

I =

Electrical Current (Amperes)

V =

Voltage (Voltage)

R =

Resistance (Ohms)

Ohm's law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Therefore, if the voltage is increased, the current will increase provided the resistance of the circuit does not change. Similarly, increasing the resistance of the circuit will lower the current flow if the voltage is not changed. The formula can be reorganized so that the relationship can easily be seen for all of the three variables.

The Java applet below allows the user to vary each of these three parameters in Ohm's Law and see the effect on the other two parameters. Values may be input into the dialog boxes, or the resistance and voltage may also be varied by moving the arrows in the applet. Current and voltage are shown as they would be displayed on an oscilloscope with the X-axis being time and the Y-axis being the amplitude of the current or voltage. Ohm's Law is valid for both direct current (DC) and alternating current (AC). Note that in AC circuits consisting of purely resistive elements, the current and voltage are always in phase with each other.

Exercise: Use the interactive applet below to investigate the relationship of the variables in Ohm's law. Vary the voltage in the circuit by clicking and dragging the head of the arrow, which is marked with the V. The resistance in the circuit can be increased by dragging the arrow head under the variable resister, which is marked R. Please note that the vertical scale of the oscilloscope screen automatically adjusts to reflect the value of the current.

See what happens to the voltage and current as the resistance in the circuit is increased. What happens if there is not enough resistance in a circuit? If the resistance is increased, what must happen in order to maintain the same level of current flow?

4 0

4 years ago

Imagine two starts are exactly the same size, but one of the stars to greater mass than the other.which star will burn out all o

Neko [114]

Answer:

The larger star will burn out faster. as nuclear fuel is burned out due to higher percentage being consumed.

Explanation:

Gravity on the other hand is only affected a little during this process and mass use. Solar mass loss is caused by mass that is turned into energy (E=mc²), but also by the material that is lost to the solar wind.

4 0

3 years ago

While the negatively charged rod is near the disk without touching it, a hand briefly touches the end of the post. Then the nega

Paraphin [41]

Answer:

that initially the weather vane was at rest, by this load that remained on the pole it would begin to move.

Explanation:

Let us carefully analyze the situation, when the bar is facing the index post a load of equal magnitude, but opposite sign on its surface, these two charges are in balance; When the hand touches the pole, it creates a path to the ground where the charges that were induced on the pole can be balanced with the charge coming from the ground, leaving a zero charge on the pole.

Now if the hand is removed, there can be no exchange of charges with the earth. When the bar is removed, the induced loads are redistributed in the post, but the excess loads that came from the earth that have the same value and are of a sign opposite to the induced ones remain, you want to sign that they are of the same sign as the charges of the bar.

In summary, after the process, the post has a load of equal magnitude and sign (negative) that of the bar.

If we assume that initially the weather vane was at rest, by this load that remained on the pole it would begin to move.

4 0

3 years ago

A student sets up an experiment to determine the inertial mass of a cart. The student has access to the following measurement eq

wlad13 [49]

Answer:

The correct answers are a and d

Explanation:

In this experiment it can be analyzed using Newton's second law

F = m a

m = F / m

The outside is supplied by the spring balance and is constant, therefore the acceleration of the system is also constant.

The acceleration can be found with the kinematic equations

x = v t + ½ a t²

As we start from rest the initial speed is zero

a = 2 x / t²

Therefore we need the reading of position and time.

Finally, the relationship between the balance reading and this acceleration of the mass of the system

Let's analyze the answers

a) True. It is one of the necessary quantities

b) False. With the equipment we cannot measure the speed directly

c) false. Acceleration is calculated

d) true. It is the other magnitude necessary for the calculation.

The correct answers are a and d

7 0

4 years ago

Read 2 more answers

Why do rivers usually have water in them, even during a drought?

Kipish [7]

Well the case with the droughts is that the water supply comes from different places such as other smaller streams and also from underground rivers .Rivers cut into saturated ground is also another reason.

7 0

4 years ago