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Electrical Engineering

How can the Internet of Things (IoT) be used to create a smart home automation system?

by EE-Expert in IoT Applications asked 5 months ago

How can the Internet of Things (IoT) be used to create a smart home automation system?

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Explain with the help of a circuit diagram, how the value of an unknown resistance can be determined using a Wheatstone bridge?
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With suitable circuit diagram, show how emfs of 2 cells can be compared using a potentiometer?

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in Current Electricity

Three identical cells, each of emf. 2V and unknown internal resistance are connected in parallel. This combination is connected to a 5 ohm resistor. If the terminal voltage across the cell is 1.5 volt. What is the internal resistance of each cell? Hence define the internal resistance of a cell?

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A battery of emf E and internal resistance r sends a current, I1 , I2 when connected to an external resistance of R1 , R2 respectively. Find the emf. and internal resistance of the battery.

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Why do we prefer a potentiometer to measure the emf of a cell rather than a voltmeter?

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in Current Electricity

In a potentiometer arrangement, a cell of emf 1.25V gives a balance point at 35.0cm length of the wire. If the cell is replaced by another cell and the balance point shifts to 63.0cm , what is the emf of the second cell?

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