A dc motor connected to a 460 V supply has an armature resistance of 0.15 ohms.Calculate
(1) The value of back emf when the armature current is 120A.
(2) The value of armature current when the back emf if 447.4V.
if a dielectric slab of dielectric constant K is introduced between the plates of a parallel plate capacitor completely , how does the energy density of the capacitor change?
A 3 m long copper wire carrying a current of 3 A.. How long does it take for an electron to drift from one end to other end ? The cross- sectional area of the wire is 2 * 10 ^ -6 m2 and the number of conduction electrons in copper is 8.5 * 10 ^ 28 m-3 .
Two point charges 2uC and -2uC are placed at points A and B 6 cm apart .
(1) Draw the equipotential surfaces of the system.
(2) Why do equipotential surface get closer to each other near the point charges?
A) 1/4 B) 4 C) 2 D) 1/2
a) q1/q2 = 1 c) q1/q2 <= 1
b) q1/q2 < 1 d) q1/q2 >= 1
A dc motor connected to a 460 V supply has an armature resistance of 0.15 ohms.Calculate
(1) The value of back emf when the armature current is 120A.
(2) The value of armature current when the back emf if 447.4V.
Q.15. Figure shows a portion of a circuit. Value of current through is
(1)
(2) 2 A
(3) 1 A
(4) 3 A
Q.88. The heat generated in the circuit after closing the switch is
(1)
(2)
(3) 2
(4) Zero
if a dielectric slab of dielectric constant K is introduced between the plates of a parallel plate capacitor completely , how does the energy density of the capacitor change?
of that through surface S1?
A 3 m long copper wire carrying a current of 3 A.. How long does it take for an electron to drift from one end to other end ? The cross- sectional area of the wire is 2 * 10 ^ -6 m2 and the number of conduction electrons in copper is 8.5 * 10 ^ 28 m-3 .
Two point charges 2uC and -2uC are placed at points A and B 6 cm apart .
(1) Draw the equipotential surfaces of the system.
(2) Why do equipotential surface get closer to each other near the point charges?