when voltage gets down the current of motor increases. but
according to Ohm's law voltage is directly proportional to
current. plz explain
Answers were Sorted based on User's Feedback
Answer / abc
If Motor is of 20 KW DC/AC Type then we can calculate P=VI,
or P=VISin* here power is constant so, V is inversely
propotional to I.
Is This Answer Correct ? | 31 Yes | 0 No |
Answer / narayana rao veeramalla
ohms law states that at constant temperature current
directly proportional to voltage and inversely to resistance
it doesn't involved any constant power concept... As the
potential you apply across the conductor increases the
current carrying electrons flow definitely increases...
here the question is for a constant power output motor...
for keeping the L.H.S constant the R.H.S two variables will
be in inversely proportionate in power equation P=VI....
Is This Answer Correct ? | 15 Yes | 0 No |
Answer / rohit kumar jha
Two type of emf's are there in motor, first one is due to the
magnetic field set up by the stator and second one is due to
the current flowing in the armature(rotor).
Due to the first emf, a current is set up in the armature,
which is resisted by the current due to the supplied
voltage.As the voltage value decreases the current decreases,
which decreases the resistance to the first current(as both
are opposite in direction), hence the value of current
increases.
It's really a nice and a tricky question :))))
Is This Answer Correct ? | 3 Yes | 0 No |
ohm's law is used only for d.c supply not for a.c supply
Is This Answer Correct ? | 6 Yes | 24 No |
On what principle reluctance motors work?
Why Neutral Busbar CT & transformer neutral CT connected with phase CT in Restricted Earth Fault?
what is the gas pressure at normal & operating conditions of sf6 cb??
what are the main applications of transistor in non-linear region?
Hoe to calculate body earthing conductor size ?
we have 15 ampere variyac but we want 30 ampere variyac what we do
what is the difference between capacitive voltage transformer & inductive voltage transformer.
A 2083kva AVR was tested, phase to ground shows continuity, what is the implications
which type of motor using in drilling machine ? & who to produce very high torque in drilling machine?
1 Answers National Drilling Company,
Define ampere
1- XC and the RC time constant are both measures of the reaction of C to a change in ____? 2-The power factor is a numerical ratio with a value between 0 and 1 equal to the ______________ of the phase angle. 3-When V and I are out of phase because of reactance, the product of V times I is called ______________ power 4-For _____________ inductors, the branch currents can be added algebraically. 5- The ______________ power in watts can be calculated as I^2R 6-Calculate XL with L = 30mH and f = 1kHz ( I have Xl=2piFL 2*3.141592653*1kHz*30mH =188 ohms Please check) 7-A parallel RL circuit has the values, R = 5kohms, XL = 5kohms. A voltage source of Vt = 10Vrms is connected in parallel to R and L. Determine the total current, It delivered by the voltage source Vt. 8-A series RC circuit has R = 1Mohm and C = 1microF. How long would it take for the capacitor to fully discharge if it is initially fully charged? 9-A circuit has real power = 300W and an apparent power of 500VA. Determine the power factor and phase angle. 10-The time constant for an LR series circuit is T = 0.1s and R = 10ohms. Calculate the inductance L.
What is the diff btw Conventional & Addressable Fire Alarm System???