Q. The magnetic flux linked with the coil (in Weber) is given by the equation- Փ = 5t2 + 3t + 16 The induced EMF in the coil at time, t=4 will be-(i) -27 V(ii) -43 V(iii) -108 V(iv) 210 V Answer: (ii) -43 V Փ = 5t2 + 3t + 16 |e|=dՓ/dt = d[5t2 […]
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Q. A conducting square loop of side ‘L’ and resistance ‘R’ moves in its plane with the uniform velocity ‘v’ perpendicular to one of its sides. A magnetic induction ‘B’ constant in time and space pointing perpendicular and into the plane of the loop exists everywhere as shown in the figure. The current induced in
Q. Two coils are placed close to each other. The mutual inductance of the pair of coils depends upon the(i) rate at which current change in the two coils(ii) relative position and orientation of the coils(iii) rate at which voltage induced across two coils(iv) currents in the two coils Answer: (ii) relative position and orientation
Q. The small angle between magnetic axis and geographic axis at a place is-(i) Magnetic meridian(ii) Geographic meridian(iii) Magnetic inclination(iv) Magnetic Declination Answer: (iv) Magnetic Declination Correct option is Magnetic declination or Angle of declination. It is the small angle between geographic axis & magnetic axis.
The small angle between magnetic axis and geographic axis at a place is Read More »
Q. The horizontal component of earth’s magnetic field at a place is √3 times the vertical component. The angle of dip at that place is(i) π/6(ii) π/3(iii) π/4(iv) 0 Answer: (i) π/6 Target law Bv = BH tanδ
Q. Two wires of the same length are shaped into a square of side ‘a’ and a circle with radius ‘r’. If they carry same current, the ratio of their magnetic moment is (i) 2 : π(ii) π : 2(iii) π : 4(iv) 4 : π Answer: (iii) π : 4
Q. The coil of a moving coil galvanometer is wound over a metal frame in order to(i) reduce hysteresis(ii) increase sensitivity(iii) increase moment of inertia(iv) provide electromagnetic damping Answer: (iv) provide electromagnetic damping The coil of a moving coil galvanometer is wound over metallic frame to provide electromagnetic damping so it becomes dead beat galvanometer.
The coil of a moving coil galvanometer is wound over a metal frame in order to Read More »
Q. The SI unit of magnetic field intensity is(i) AmN-1(ii) NA-1m-1(iii) NA-2m-2(iv) NA-1m-2 Answer: (ii) NA-1m-1
Q. The equivalent resistance between A and B is- (i) 3 ohms(ii) 5.5 ohms(iii) 7.5 ohms(iv) 9.5 ohms Answer: (iii) 7.5 ohms
Q. If the potential difference V applied across a conductor is increased to 2V with its temperature kept constant, free electrons in a conductor will –(i) remain the same(ii) become half of its previous value(iii) be double of its initial value(iv) become zero. Answer: (iii) be double of its initial value If temperature is kept