Category: electricity

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#10yearschallenge

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Meanwhile in Serbian Orthodox churches

Pantograph and TrainsPantograph is a very interesting device…

Pantograph and Trains

Pantograph is a very interesting device that you may find on the roof of electric trains, trams or electric buses.

And the primary purpose that it serves is to collect power from the overhead power line to run the motors of the train without losing contact at higher speeds.

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The train takes the current
from the over head line and the current flows to the tracks
which are earthed at regular intervals via the axle brush on the train.

This completes the circuit.

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                                               Source

The overhead lines are kept in tension and dropper wires are placed at multiple locations to ensure that the contact wire does not bend under its own weight.

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And since any two objects that rub against each other, constant frictional contact would wear them out, the Pantograph and the contact wires have a sliding contact.

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This results in less wear for both the Pantograph and the contact wires resulting in lesser maintenance.

Graphite conducts electricity extremely well while also working great as a lubricant due to it’s self-lubricating properties and therefore most contact strips on the Pantographs are made up of Graphite.

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It’s a very simple apparatus with an extremely pivotal role and that’s what makes  the Pantograph special. Have a great day!

* Trolley pole

** Third Rail

*** Arcing is a serious problem when we are dealing with any high voltage lines. in bullet trains which operate under higher voltages, the Pantographs are always forced to be in contact with the contact wires through a dynamic lever-spring mechanism. (Source)

How Do Volcanoes Make Lightning? “Volcanic li…

How Do Volcanoes Make Lightning?

“Volcanic lightning appears to occur most frequently around volcanoes with large ash plumes, particularly during active stages of the eruption, where flowing, molten lava creates the largest temperature gradients. The phenomena of lightning has been exquisitely recorded around a number of recent volcanic eruptions, including Iceland’s Eyjafjallajökull, Japan’s Sakurajima, Italy’s Mt. Etna, and Chile’s Puyehue, Calbuco and Chaiten volcanoes. But what you may not know is this phenomenon was not only captured during Mt. Vesuvius’ last eruption in 1944, but was accurately described nearly 2,000 years ago when it erupted all the way back in the year 79!”

Volcanoes are some of the most potentially destructive natural phenomena known to occur on our world. The most violent eruptions feature not only lava, but soot, ash, volatile gases, and even enormous chunks of rock hurled great distances. What you might not realize, however, is just how frequently these eruptions are accompanied by another spectacular show: volcanic lightning. Lightning isn’t only found in thunderstorms or other great electrical discharges between the clouds and the ground, but is produced in volcanic eruptions all throughout the world, and throughout history as well. After countless generations, where we wondered what could produce such an unusual but spectacular show, we’ve finally figured it out.

Come get the science behind how volcanoes make lightning, and enjoy some of the greatest photographs of this phenomena humanity’s ever taken!

Might be a dumb question: But why charger always heat up? Thanks !

Not a dumb question at all. Imagine the charger to be this conversion box :

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The only problem being that the efficiency of this conversion from AC to DC is only ~ (80-85)%.

The rest of the energy is lost due to the resistance offered by the wires and transistors which gets reflected as heat or I2R loses. So, higher the resistance, more the loss.

Thanks for asking !

Hola ur blog is so cool and I think it’s really cool you like to help people. I’m a bit confused on what power is in a circuit and it’s relationship to current, resistance, and voltage… can you help explain? Tysm!!

The Hydraulic Analogy

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There are a couple of times especially in engineering where it is easier to think of DC electric circuits in terms of hydraulic circuits and vice versa. And I think in this case it might help you as well.

Current: The amount of water flowing through a section of a pipe over time

Voltage: The difference in pressure between two points in the water circuit.

Resistance: Narrow constrictions offer high resistance and every pipe like every other wire offers resistance to the flow of water.

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Power: It is the rate at which the energy stored in the water is used to drive a mechanical device like a water wheel.

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Think of it like this: How fast the wheel is going to spin is dependent on the amount of water hitting it (current) and how much pushing this quantity of water does (voltage). 

(pressure = force applied / area)

Hope this helps and I am glad that you are finding the blog to be useful. Cheers!

* More about the water analogy for electric circuits

** Where does this analogy fail ? (Very important to know)

Hola ur blog is so cool and I think it’s really cool you like to help people. I’m a bit confused on what power is in a circuit and it’s relationship to current, resistance, and voltage… can you help explain? Tysm!!

The Hydraulic Analogy

image

There are a couple of times especially in engineering where it is easier to think of DC electric circuits in terms of hydraulic circuits and vice versa. And I think in this case it might help you as well.

Current: The amount of water flowing through a section of a pipe over time

Voltage: The difference in pressure between two points in the water circuit.

Resistance: Narrow constrictions offer high resistance and every pipe like every other wire offers resistance to the flow of water.

image

Power: It is the rate at which the energy stored in the water is used to drive a mechanical device like a water wheel.

image

Think of it like this: How fast the wheel is going to spin is dependent on the amount of water hitting it (current) and how much pushing this quantity of water does (voltage). 

(pressure = force applied / area)

Hope this helps and I am glad that you are finding the blog to be useful. Cheers!

* More about the water analogy for electric circuits

** Where does this analogy fail ? (Very important to know)