Answer / sanjay

An UPS is a device that allows a computer to keep running for at least a short time when primary power is lost. it also provides protection from power surges.
thats converting incoming AC to DC through a rectifier and converts it back with an inverter.

We all know about DC concept,i.e +ve connected to +ve ,-ve connected to -ve. If landline phones lines are dc lines,then how it works even if the polarties are interchanged??

1 Answers   Infosys,

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Why RX LEVEL is Negative in GSM????

2 Answers   NSN, Wipro,

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Suppose, I m talking with mine friend and I m going to market by car(setting).After some distance passed, mine call will be handover to other site, this site allready going on with full trafic than mine call will be drop or handover to the same site .....

6 Answers   Airtel,

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Why would the files on hard drive stores temporarily but not permanent?

0 Answers  

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Name the breakdown mechanism in a lightly doped p-n junction under reverse biased condition.

0 Answers  

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What are the two types of control strategies?

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what is amplifier?

0 Answers  

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Why EMI is very low in optical fiber,while frequency is very high? As we no that in general condition frequency inversely proportional to EMI.

2 Answers   IIT,

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In 7-segment display system, zero blanking is used to blank out A All the leading zeros B All the trailing zeros C The zero in the MSB(location) D a and b

1 Answers  

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iam B.E 1year student,actually i have a habit i.e anything to think pratically but always iam in confusion what i have to do

2 Answers  

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What are the two methods of control in ac voltage controllers?

0 Answers  

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What will happen if we change the polarity of microwave antenna?

0 Answers   NSN,

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