ISC Class 12 Moving Charges and Magnetism — practice questions
51 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice ISC Class 12 Moving Charges and Magnetism in the app →A point charge moves with velocity v in a region having both an electric field E and a magnetic field B. The tA charged particle is at rest in a region of uniform magnetic field B. The magnetic force acting on it is:A positive charge moves with speed v parallel to a uniform magnetic field B. The magnetic force on the charge A magnetic field B is along the +y axis and a proton moves along the +x axis. The direction of the magnetic foThe SI unit tesla (T) for magnetic field is equivalent to:One gauss equals which of the following in tesla?A straight wire of mass 200 g and length 1.5 m carries a current of 2 A. It is held in mid-air, its weight balA straight conductor of length l carrying current I is placed in a uniform magnetic field B so that the currenA 3.0 cm wire carrying a current of 10 A is placed inside a solenoid, perpendicular to its axis, where the fieA charged particle enters a uniform magnetic field with its velocity exactly perpendicular to the field. The pA particle of charge q and mass m moves with speed v perpendicular to a uniform field B, describing a circle. An electron (mass 9 × 10⁻³¹ kg, charge 1.6 × 10⁻¹⁹ C) moves at 3 × 10⁷ m s⁻¹ perpendicular to a field of 6 × 1An electron of mass 9 × 10⁻³¹ kg moves at 3 × 10⁷ m s⁻¹. Its kinetic energy, given 1 eV = 1.6 × 10⁻¹⁹ J, is apA particle of charge q and mass m undergoes circular motion in a uniform magnetic field B. Its frequency of reIf the speed of a charged particle moving perpendicular to a uniform magnetic field is doubled, its cyclotron A charged particle moves in a uniform field B such that its velocity has a component v∥ parallel to B. The disAn electron is shot into a uniform field of 6.5 G (1 G = 10⁻⁴ T) at 4.8 × 10⁶ m s⁻¹ normal to the field. With According to the Biot–Savart law, the magnitude of the field dB produced by a current element I dl at distanceThe proportionality constant μ₀/4π in the Biot–Savart law has the exact SI value:A current element Δl = Δx î (Δx = 1 cm) at the origin carries a current I = 10 A. The magnetic field at a poinUsing the Biot–Savart law, the magnetic field at the centre of a circular loop of radius R carrying current I A tightly wound coil of 100 turns and radius 10 cm carries a current of 1 A. The magnitude of the magnetic fieA wire carrying current 12 A is bent into a semicircular arc of radius 2.0 cm. The magnetic field at the centrIn Example 4.5, a current-carrying wire has straight segments meeting at the centre of a semicircular arc. TheAmpère's circuital law for a closed loop bounding a surface carrying total current I is correctly stated as:Using Ampère's law, the magnetic field at a perpendicular distance r from a long straight wire carrying currenA long straight wire carries a current of 35 A. The magnitude of the magnetic field at a point 20 cm from the A long straight wire of circular cross-section (radius a) carries a uniformly distributed steady current I. FoThe magnetic field inside a long solenoid having n turns per unit length and carrying current I is:A solenoid of length 0.5 m and radius 1 cm has 500 turns carrying a current of 5 A. The magnitude of the fieldA closely wound solenoid 80 cm long has 5 layers of 400 turns each and carries a current of 8.0 A. The magnituTwo long parallel wires carry currents in the same direction. The force between them is:Two long parallel wires a distance d apart carry currents Iₐ and I_b. The magnitude of the force per unit lengThe ampere is defined as the steady current which, maintained in two long parallel wires 1 m apart in vacuum, Two long parallel wires A and B carry currents 8.0 A and 5.0 A in the same direction, separated by 4.0 cm. TheA long straight conductor carrying 1 A lies on a horizontal table. The horizontal component of the earth's fieA planar current loop of N turns, area A, carrying current I, has magnetic moment:A current loop of magnetic moment m is placed in a uniform field B so that m makes angle θ with B. The torque A current loop of magnetic moment m is placed in a uniform magnetic field B. The net force on the loop is:A 100-turn circular coil of radius 10 cm carries a current of 3.2 A. Its magnetic moment is approximately:A 100-turn coil of radius 10 cm carrying 3.2 A (moment 10 A m²) sits in a 2 T field, free to rotate. The torquA square coil of side 10 cm with 20 turns carries 12 A. Its normal makes 30° with a uniform horizontal field oFor a current loop placed in a uniform field, the orientation of stable equilibrium is the one where:On the axis of a circular current loop of radius R, at a distance x ≫ R, the magnetic field can be written in In a moving coil galvanometer with a radial field, the magnetic torque NIAB is balanced by the spring's counteIn a moving coil galvanometer the magnetic field is made radial chiefly so that:A moving coil galvanometer is converted into an ammeter by connecting:The current sensitivity of a moving coil galvanometer (deflection per unit current) is:In a galvanometer, the number of turns N is doubled (so resistance also doubles). The voltage sensitivity thenA galvanometer of resistance 60.00 Ω is used to measure current in a circuit with a 3 V source and a 3 Ω resisThe 60 Ω galvanometer of the previous setup is converted to an ammeter with a shunt rₛ = 0.02 Ω, then placed i