Answer / sarav3387

DC voltage has either -ve OR +ve polarity. in case,
you connect +ve polarity to ground and -ve polarity to
source, at that time it produces negative DC voltage.
A negative DC supply usually is used along with an
positive supply in audio electronics in order to produce an
AC output (both positive and negative voltage excursions
with respect to the zero volt level) which represents the AC
nature of the typical audio input signal. The only other use
for a negative supply voltage that I can think of is mostly
a thing of the past but old fashioned ram chips required a
+5, +12, and -12v supplies.

Answer / alok gangwar

A negative line voltage helps to reduce the corrosion from
electrochemical reactions occurring on a wet telephone
line. Also -48v DC is more stable than +48 volit, so -48 V
is preferred.

Answer / tinu

negative dc means voltage is at negative potential and
vice-versa for positive dc.

Answer / balaji

Negative & Positive polority plays major role in case of
Electronics Devices.We may aware of simple electronics
components Diode,Transistor,etc are made of PN junctions.
For proper conductions & baising,Blocking Polority of the
circuits is very important

Answer / answr

These +ve and -ve supply are much more Important in power plants and oil and gas refinery.. This is because the energy level of both. +ve supply have much more energy than -ve supply. So normaly we grounded the +ve supply and -ve supply is used for supply. When we connect the +ve supply to supply this will cause produce some fire when some short connection occur in the equipments. So these fire will cause to explosion of oil and gas plants. For this reason we connect the -ve supply to the equipments.

Answer / faize

NPN types Transisters is faster than PNP types so Modern
Electronics Devices using -ve Dc dydtem in whitch the +ve
terminal connect to the ground(zero potential)so as to get
negatvie supply voltage.

Answer / shakeel

i think when we supply positve potential then we found
positive output voltage and vicewarsa

Answer / karthikeyn m

Negative & positive polarity are two different potential
with repect to earth and the current flow's in different
direction.

Answer / purushmallya

Parameter Voltage is measured with respect to a point so if
a voltage is negetive at some point means it has so much
potential down with respect to the measured point. And all
Electronic circuitory works at perticular potential
difference.

Answer / jagadisha.n bmsit

+ve and -ve voltages is as per our reference. For ex in ac
particular reference both +ve and -ve apper in one cycle
and -ve is nothing but voltage in opposite polarity of +ve
voltage from the ref thats it. Some electronic peak to peak
voltage(say +/- 12V) in case of amplifier to turn on and
some of the device req only +ve/-ve vltage.

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