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?
Answer Posted / 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 |
Post New Answer View All Answers
what is p.s impedance measurement test in earthing transformer?
Dear All, I am new in construction company , my boss ask a question at time of interview , If we have 60MW generation and Single Power Transformer step-up we have. if CMR 50/60MVA , ONAN, ONAF respectively , is it sufficient or not ? for that much power to transfer,
what is the profesional board for electrical engineer what is thepast and during construction for electrical engineering
what is the IS foe lightning arrester?
What is core CT & it's function?
Why we cant store an ac power. If we coo store in which device we can?
What are the factor to be consider for CT selection in 132kV substation?
i have attended the interview on 4th June,08 at Kolkata in IOCL, can anybody tell me what is its result
If we use 250A MCCB as a incomer in Control panel for a fault level of 50kA for one second ,assuming temperature rise from 85 Deg. to 100 Deg , Then what will be the Aluminium Bus-bar size for 250A MCCB? Explain in detail.
The inventer is a battery, but if lost current at home u will turn on the fan but the is AC and inventer battery is dc . Then how the fan was rotating. What device Or machine in fan converst the Dc power to Ac power
what happen if the load connected to the induction motor is taken away? the same question for synchoronous generator in synch i think that the the exitation voltage will appear on the terminal only if so plz answer me
How will you justify IR value and Charging voltage of any motor,transformer and Cables.......???? . . . . . . . . Plz tell me any body Baljeet Singh, engineer_89@refiff.com
1.WHAT IS A SMART CAPABLE DB ( DISTRIBUTION BOX) ? 2. HOW TO DECIDE THE TYPE OF DB TO BE USED ( RECESSED/ PLUG TYPE/ SMART ETC ETC? 3. WHAT IS MILLENEUM BUS BAR USED IN DB? 4.DIFFERENTIATE MCCB AND MCB.
Pl. brief about break-down maintenance of machine tool.
what is the preventive maintence for ht panels and busbars and vcb abd acb's.