Description : Calculate the emf of a coil with turns 100 and flux rate 5 units. a) 20 b) -20 c) 500 d) -500
Last Answer : d) -500
Description : Find the emf induced in a coil of 60 turns with a flux rate of 3 units. a) -60 b) -180 c) 60 d) 180
Last Answer : b) -180
Description : Calculate the emf of a material having flux density 5sin t in an area of 0.5 units. a) 2.5 sin t b) -2.5 cos t c) -5 sin t d) 5 cos t
Last Answer : d) 5 cos t
Description : Consider the conductor to be a coil of turns 60 and the flux density to be 13.5 units, current 0.12A and area 16units. The torque will be a) 1555.2 b) 1222.5 c) 525.1 d) 255.6
Last Answer : a) 1555.2
Description : Calculate the emf in a material with flux linkage of 3.5t 2 at 2 seconds. a) 3.5 b) -7 c) -14 d) 28
Last Answer : c) -14
Description : Calculate the emf of a material having a flux linkage of 2t 2 at time t = 1second. a) 2 b) 4 c) 8 d) 16
Last Answer : b) 4
Description : Calculate the emf when the flux is given by 3sin t + 5cos t a) 3cos t – 5sin t b) -3cos t + 5sin t c) -3sin t – 5cos t d) 3cos t + 5sin t
Last Answer : b) -3cos t + 5sin t
Description : Find the flux contained by the material when the flux density is 11.7 Tesla and the area is 2 units. a) 23.4 b) 12.3 c) 32.4 d) 21.3
Last Answer : a) 23.4
Description : Identify which of the following is the unit of magnetic flux density? a) Weber b) Weber/m c) Tesla d) Weber -1
Last Answer : c) Tesla
Description : Find the force due to a current element of length 2cm and flux density of 12 tesla. The current through the element will be 5A. a) 1 N b) 1.2 N c) 1.4 N d) 1.6 N
Last Answer : b) 1.2 N
Description : Calculate the flux density due to a circular conductor of radius 100nm and current 5A in air. a) 10 b) 100 c) 0.1 d) 1
Last Answer : a) 10
Description : Find the inductance of a coil with permeability 3.5, turns 100 and length 2m. Assume the area to be thrice the length. a) 131.94mH b) 94.131mH c) 131.94H d) 94.131H
Last Answer : a) 131.94mH
Description : Find the electric field applied on a system with electrons having a velocity 5m/s subjected to a magnetic flux of 3.6 units. a) 15 b) 18 c) 1.38 d) 0.72
Last Answer : b) 18
Description : The induced emf in a material opposes the flux producing it. This is a) Faraday law b) Ampere law c) Lenz law d) Curie law
Last Answer : c) Lenz law
Description : A coil of 500 turns is linked with a flux of 25 mwb, when carries a current of 12.5A. Calculate the value of self-inductance.
Last Answer : Ans: Self-Inductance: L = NΦ /I = 500 × 25 × 10-3 / 12.5 = 1 H
Description : The inductance is the measure of a) Electric charges stored by the material b) Emf generated by energising the coil c) Magnetic field stored by the material d) Magnetization of dipoles
Last Answer : c) Magnetic field stored by the material
Description : Find the total flux in a coil of magnetic flux density 12 units and area 7 units. a) 0.84 b) 0.96 c) 8.4 d) 9.6
Last Answer : a) 0.84
Description : Calculate the magnetic moment when a field of B= 51 units is subjected to a torque of 20 units. a) 0.39 b) 4.2 c) 2.55 d) 3.21
Last Answer : a) 0.39
Description : Calculate the reluctance of the material with a mmf of 3.5 units and flux of 7units. a) 32.5 b) 10.5 c) 0.5 d) 2
Last Answer : b) 10.5
Description : Calculate the displacement current density when the electric flux density is 20sin 0.5t. a) 10sin 0.5t b) 10cos 0.5t c) 20sin 2t d) 20cos 2t
Last Answer : b) 10cos 0.5t
Description : The expression for the inductance in terms of turns, flux and current is given by a) L = N dφ/di b) L = -N dφ/di c) L = Niφ d) L = Nφ/i
Last Answer : a) L = N dφ/di
Description : Calculate damped natural frequency, if a spring mass damper system is subjected to periodic disturbing force of 30 N. Damping coefficient is equal to 0.76 times of critical damping coefficient and undamped natural frequency is 5 rad/sec A. 3.99 rad/sec B. 2.13 rad/sec C. 4.12 rad/sec D. 3.24 rad/sec
Last Answer : D. 3.24 rad/sec
Description : The energy of a coil depends on the turns. State True/False. a) True b) False
Last Answer : a) True
Description : The force on a conductor of length 12cm having current 8A and flux density 3.75 units at an angle of 300 is a) 1.6 b) 2 c) 1.4 d) 1.8
Last Answer : d) 1.8
Description : Calculate the conduction density of a material with resistivity of 0.02 units and electric intensity of 12 units. a) 300 b) 600 c) 50 d) 120
Last Answer : b) 600
Description : Calculate the Larmer angular frequency for a magnetic flux density of 12.34 x 10 -10 . a) 108.36 b) 810.63 c) 368.81 d) 183.36
Last Answer : a) 108.36
Description : Calculate the energy when the magnetic intensity and magnetic flux density are 15 and 65 respectively. a) 755 b) 487.5 c) 922 d) 645
Last Answer : b) 487.5
Description : Calculate the energy in an electric field with flux density 6 units and field intensity of 4 units. a) 12 b) 24 c) 36 d) 48
Last Answer : a) 12
Description : Find the flux density due to a conductor of length 6m and carrying a current of 3A(in 10 -7 order) a) 1 b) 10 c) 100 d) 0.1
Last Answer : a) 1
Description : Which of the following will produce an induced emf: a. Changing area of coil b. Changing magnetic flux c. changing orientation of coil d. all of them
Last Answer : c. changing orientation of coil
Description : The current flowing in a coil due to induced emf depends upon: a. shape of coil b. resistance of coil c. area of coil d. magnetic flux
Last Answer : a. shape of coil
Description : Find the inductance of a material with 100 turns, area 12 units and current of 2A in air. a) 0.75mH b) 7.5mH c) 75mH d) 753mH
Last Answer : a) 0.75mH
Description : Find the induced EMF in an inductor of 2mH and the current rate is 2000 units. a) 4 b) -4 c) 1 d) -1
Last Answer : b) -4
Description : The equivalent inductances of two coils 2H and 5H in series aiding flux with mutual inductance of 3H is a) 10 b) 30 c) 1 d) 13
Last Answer : d) 13
Description : Calculate the reluctance of a material with length 2π x 10 -4 in air with area 0.5. a) 1 b) 10 c) 100 d) 1000
Last Answer : d) 1000
Description : Calculate the polarisation vector of the material which has 100 dipoles per unit volume in a volume of 2 units. a) 200 b) 50 c) 400 d) 0.02
Last Answer : a) 200
Description : Find the magnetic field intensity due to a solenoid of length 12cm having 30 turns and current of 1.5A. a) 250 b) 325 c) 175 d) 375
Last Answer : d) 375
Description : A closely coiled helical spring of radius R, contains n turns and is subjected to an axial load W. If the radius of the coil wire is r and modulus of rigidity of the coil material is C, the deflection of the coil is (A) WR3n/Cr4 (B) 2WR3n/Cr4 (C) 3WR3n/Cr4 (D) 4WR3n/Cr
Last Answer : (D) 4WR3n/Cr
Description : A closely coiled helical spring of radius R, contains n turns and is subjected to an axial loadW. If the radius of the coil wire is r and modulus of rigidity of the coil material is C, the stress developed in the helical spring is (A) WR/ 3 (B) 2WR/ 3 (C) 2WR/ 2 (D) 4WR/ 2
Last Answer : (B) 2WR/ 3
Description : The close-coiled helical springs ‘A’ and ‘B’ are of same material, same coil diameter, same wire diameter and subjected to same load. If the number of turns of spring ‘A’ is half that of spring ‘B’, the ratio of deflection of spring ‘A’ to spring ‘B’ is (a)1/2 (b) 1 (c) 2 (d) 4
Last Answer : (a)1/2
Description : E.M.F for a coil depends upon A. the cross sectional area B. no. of turns of wire C. the magnitude of magnetic flux density D. all of above
Last Answer : all of above
Description : A 4 pole lap wound dc shunt motor rotates at the speed of 1500 rpm, has a flux of 0.4 mWb and the total number of conductors are 1000. What is the value of emf? (A) 100 Volts. (B) 0.1 Volts. (C) 1 Volts. (D) 10 Volts.
Last Answer : Ans: D Given N = 1500 rpm, Φ = 0.4 mWb, Z = 1000, P = 4, & A= 4 Therefore, Eb = NΦPZ / 60 A = 1500 x 0.4 x 4 x 1000 x 10^-3 / 60 x 4 = 60/6 = 10 volts
Description : Find the conduction current density of a material with conductivity 200units and electric field 1.5 units. a) 150 b) 30 c) 400/3 d) 300
Last Answer : d) 300
Description : Find the current density of a material with resistivity 20 units and electric field intensity 2000 units. a) 400 b) 300 c) 200 d) 100
Last Answer : d) 100
Description : Calculate the power of a material with electric field 100 units at a distance of 10cm with a current of 2A flowing through it. a) 10 b) 20 c) 40 d) 80
Last Answer : b) 20
Description : Please ripley me due to emergency
Last Answer : To calculate the flux density in the ring, you need to use the following formula: B = (μ * I * N) / (2 * π * r) where: B is the flux density in the ring (in teslas) μ is the relative permeability ... 2 * π * 0.127 m) = 0.53 T So the flux density in the ring would be approximately 0.53 teslas.
Description : Find the magnetic field when a circular conductor of very high radius is subjected to a current of 12A and the point P is at the centre of the conductor. a) 1 b) ∞ c) 0 d) -∞
Last Answer : c) 0
Description : Which of the following relations is correct? a) MMF = ∫ B.dl b) MMF = ∫ H.dl c) EMF = ∫ E.dl d) EMF = ∫ D.dl
Last Answer : c) EMF = ∫ E.dl
Description : The line integral of the electric field intensity is a) Mmf b) Emf c) Electric potential d) Magnetic potential
Last Answer : b) Emf
Description : The energy in a magnetic material is due to which process? a) Emf b) Magnetization c) Magnetostriction d) Polarization
Last Answer : b) Magnetization