CBSE Class 12 Moving Charges and Magnetism — practice questions
70 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice CBSE Class 12 Moving Charges and Magnetism in the app →A proton moves north at $10^6$ m/s in a magnetic field of $0.1$ T pointing east. The magnetic force on it is:A long straight wire carries $5$ A. The magnetic field $0.10$ m away from the wire is:A solenoid has $500$ turns per metre and carries $2$ A. Field inside is:The cyclotron frequency of a particle of mass $m$ and charge $q$ in field $B$ is:Oersted's 1820 experiment showed that a current-carrying wire produces a noticeable effect on a nearbyThe magnetic force on a charge $q$ moving with velocity $\vec{v}$ in a magnetic field $\vec{B}$ isA positive charge moves with velocity $\vec{v}$ PARALLEL to a uniform magnetic field $\vec{B}$. The magnetic fThe Biot-Savart law gives the magnetic field $d\vec{B}$ due to a small current element $I\,d\vec{l}$ at a poinThe magnetic field at the CENTRE of a circular current loop of radius $R$ carrying current $I$ isInside a long solenoid carrying current $I$ with $n$ turns per unit length, the magnetic field isAmpere's Circuital Law states that around any CLOSED loop, the line integral of $\vec{B}\cdot d\vec{l}$ equalsA charged particle (charge $q$, mass $m$) moves in a circle perpendicular to a uniform magnetic field $B$. TheTwo long parallel wires separated by distance $d$ carry currents $I_1$ and $I_2$ in the SAME direction. The foA current loop of area $A$ carrying current $I$ has a MAGNETIC MOMENT of magnitudeA moving-coil galvanometer measures current by exploiting which physical principle?A charged particle enters a region of crossed electric and magnetic fields ($\vec{E}\perp\vec{B}$). For the paA charged particle of mass $m$ and charge $q$ enters a uniform magnetic field $B$ with velocity $\vec{v}$ at aThe magnetic field at a distance $r$ from a LONG STRAIGHT wire carrying current $I$ isA charged particle moves with velocity v parallel to a uniform magnetic field B. The magnetic force on the parA circular loop of radius R carries current I. The magnitude of the magnetic field at its centre isThe angular frequency of a particle of charge q and mass m moving in a cyclotron with magnetic field B isTwo long parallel wires carry currents in the same direction. They willThe magnetic field inside an ideal long solenoid with n turns per unit length carrying current I isIn a crossed E and B velocity selector, a charged particle of speed v passes undeflected when v equalsA proton of mass m, charge e, speed v enters a magnetic field B perpendicular to its velocity. The radius of iA rectangular current loop is placed in a uniform magnetic field. The net force on the loop isA circular coil of N turns and radius R carries current I. Its magnetic dipole moment isThe magnitude of the magnetic field at perpendicular distance r from an infinite straight wire carrying currenThe magnetic field inside a toroidal solenoid with N total turns, mean radius r, carrying current I isThe period of revolution of a charged particle moving in a uniform magnetic field perpendicular to its velocitA 0.5 m wire carrying 2 A is placed perpendicular to a 0.4 T magnetic field. The force on the wire isTwo long parallel wires 0.1 m apart carry 5 A and 10 A in the same direction. The force per unit length on eacAt equilibrium, the deflection ϕ of a moving coil galvanometer with N turns, area A, current I, in a radial maAn electron enters a uniform magnetic field B at angle θ to B with speed v. The pitch of its helical path isA cyclotron of dee radius R accelerates ions of charge q, mass m in a magnetic field B. The maximum kinetic enA circular loop of radius R carries current I. The magnetic field at a point on its axis at distance x from thAt the very end of a long solenoid, the magnetic field along the axis isA magnetic dipole with moment m makes angle θ with a uniform field B. The torque on the dipole has magnitudeAn electron moves east in a magnetic field directed north. The magnetic force on the electron pointsTwo coaxial circular loops of radii R and 2R carry equal currents in the same sense. The ratio of the magneticA cyclotron operates at frequency f in a magnetic field B. The charge-to-mass ratio of the accelerated ion isThe current sensitivity of a moving coil galvanometer with N turns, coil area A, magnetic field B, spring consA 0.1 m radius loop carries 5 A. The magnetic field at a point on its axis 0.1 m from the centre is approximatA bar magnet with N pole pointing right is placed near a circular current loop whose magnetic moment also poinCyclotrons are not used to accelerate electrons becauseA long solenoid has 1000 turns per metre and carries 2 A. The magnetic field strength inside isA square coil of side 0.1 m, with 50 turns, carries 1 A in a 0.2 T field. The maximum torque on the coil isA charge q moves with velocity v through a region with electric field E and magnetic field B. The net electromThe force on a charge moving in electric and magnetic fields is named after:The magnetic force on a charge depends on its charge, its velocity and the:Compared with a positive charge, the force on a negative charge is:The magnetic force involves which product of velocity and field?To find the force on a current, the rod considered has uniform:With carrier density n, area A and length l, the number of carriers is:All known magnetic fields are due to moving charges and to intrinsic:The law giving the field of a current element is named after Biot and:By the Biot-Savart law, the field of a current element is proportional to the:The Biot-Savart field falls off with distance as its:The Biot-Savart field direction is perpendicular to the plane containing dl and:Ampere's circuital law is an alternative way of expressing the law of:Ampere's circuital law considers a surface that is:Ampere's law is to Biot-Savart law what Gauss's law is to the law of:Ampere's circuital law holds for loops that are:Ampere's law is easiest to apply in situations of high:The two pieces of equipment used to generate magnetic fields are the toroid and the:The machine that combines a solenoid and a toroid for high fields is the:A toroid is a hollow ring wound closely with many:A toroid can be viewed as a solenoid that has been:A galvanometer becomes an ammeter by adding a shunt resistance in:A galvanometer becomes a voltmeter by adding a large resistance in: