power is the product of voltage and current.so we can
measure the value of power just by using ammeter and
voltmeter.......then why do we use a wattmeter?
Answers were Sorted based on User's Feedback
Answer / gajanan
apperent power = voltage X current,
we can calculate apperent power by ammeter and voltmeter
reading but
real power = voltage X current X power factor
to measure real power we need wattmeter
Is This Answer Correct ? | 24 Yes | 1 No |
Answer / nageshwaran.n
No doubt, we could use Voltmeter & Ammeter for calculating
Power but only Apparent Power that too at that instant.
Apparent power = voltage X current,
Actual RMS Power (real power) = voltage X current X power
factor
And to measure real power we need Wattmeter only.
Is This Answer Correct ? | 11 Yes | 0 No |
Answer / smita
RIGHT POWER IS VOLTAGE X CURRENT BUT FROM THIS WE GET ONLY
APPERENT POWER,AND WE REQIRE REAL POWER I.E VOLTAGE X
CURRENT X POWE3R FACTOR AND FOR THAT WE REQUIRE WATTMETER
Is This Answer Correct ? | 6 Yes | 0 No |
Answer / pillay
Yes as all have already said you dont need to use a watt meter
only if the circuit uses a Direct Current voltage and you can
calculate the power mentally by just looking at the voltmeter and ammeter.
Is This Answer Correct ? | 1 Yes | 0 No |
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