Description : Work done by a uniform magnetic field in moving a charged particle in a circular path is a) qvB sin θ b) mg sin θ c) zero d) mg cos θ
Last Answer : Zero
Description : The expression F⃗ = qE⃗⃗ + q(v⃗ × B⃗⃗) represents _________ force a) Maxwell b) Gravitational c) Magnetic d) Lorentz
Last Answer : d) Lorentz
Description : When a uniform magnetic field B is applied to a current carrying coil, the coil will rotate in such a manner that its plane a) becomes parallel to B b) becomes anti-parallel to B c) makes an angle of 600 with B d) becomes perpendicular to B
Last Answer : d) becomes perpendicular to B
Description : The number of electric field lines passing through a certain element of area is called: (a) Electric lines of force (b) Electric intensity (c) Electric flux (d) None of these
Last Answer : (c) Electric flux
Description : iv) A rectangular coil free to rotate is placed in uniform magnetic field with its plane parallel to the magnetic lines of force. Then the coil willa) rotate to maximize the magnetic flux through ... since the magnetic flux through its plane is zero.d) experience the constant torque equal to NBIA
Last Answer : iv) A rectangular coil free to rotate is placed in uniform magnetic field with its plane parallel ... d) experience the constant torque equal to NBIA
Description : A wire loop is moved parallel to a uniform magnetic field. The induced emf in the loop: a. depends on the shape b. depends on area c. depends on nature of loop d. zero
Last Answer : d. zero
Description : A current of 5.8 A flows through a 0.25 m long straight conductor which is kept perpendicular in a region of uniform magnetic field of 3.7 T . The force on conductor is a) 5.4 N b) 2.4 N c) 3.4 N d) 6.4 N
Last Answer : a) 5.4 N
Description : Fleming's left hand rule is used to find (a) direction of magnetic field due to current carrying conductor (b) direction of flux in a solenoid (c) direction of force on a current carrying conductor in a magnetic field (d) polarity of a magnetic pole
Last Answer : (c) direction of force on a current carrying conductor in a magnetic field
Description : Which of the following is a vector quantity ? (a) Relative permeability (b) Magnetic field intensity (c) Flux density (d) Magnetic potential
Last Answer : (b) Magnetic field intensity
Description : In motor a permanent magnet provides: a. Electric field b. electric flux c. magnetic field d. gravitational field
Last Answer : d. gravitational field
Description : ___________ is not affected by a magnetic field a) Change in magnetic flux b) a moving electron c) a stationary proton d) current flowing in a conductor
Last Answer : c) a stationary proton
Description : The space around the charge within which other charges are influenced by it is called: (a) Electric field (b) Magnetic field (c) Electric flux (d) Electric intensity
Last Answer : a) Electric field
Description : The magnetic field is _________ inside a solenoid a) Zero b) uniform c) non-uniform d) infinite
Last Answer : b) uniform
Description : A proton and a α particle enter a region having a perpendicular uniform magnetic field. The ratio of time period of proton (τp) to time period of α particle (τα) is a) 1:4 b) 4:1 c) 2:1 d) 1:2
Last Answer : d) 1:2
Description : A magnetic screw placed in a non-uniform magnetic field experiences a) force and torque b) only torque c) only force d) None of these
Last Answer : a) force and torque
Description : An electron moves with a velocity of 2 × 106 ms-1 in the direction of a uniform magnetic field of 0.8 Tesla. The force on electron is a) 8 N b) 2 N c) 4 N d) Zero
Last Answer : d) Zero
Description : The pole faces of U-shaped magnet in a moving coil galvanometer are made concave to a) decrease the strength of magnetic field b) create a non-uniform magnetic field c) make the magnetic field radial d) All of these
Last Answer : c) make the magnetic field radial
Description : A proton moves in a uniform magnetic field in a circular path of radius R. If the energy of proton is doubled then the new radius becomes a) R √2 b) 2R c) R 2 d) √2 R
Last Answer : d) √2 R
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 : The current I passing through the galvanometer coil is related to the angle of deflection θ as a) I ∝ θ b) I 1/∝ θ c) I ∝ θ 2 d) I 1/∝ θ 2
Last Answer : a) I ∝ θ
Description : When field is parallel to plane of area, magnetic flux through coil isA. zero B. infinite C. 2 D. 5
Last Answer : zero
Description : In the plane of AC generator coil is parallel to the field, then emf induced in coil is: a. maximum b. minimum c. zero d. intermediate
Last Answer : b. minimum
Description : In the plane of the A.C generator coil is perpendicular to the field, then induced emf in the coil is: a. Maximum b. minimum c. zero d. intermediate value
Description : Magnetic flux linked with a coil can be changed by using an: a. Permanent magnet b.Bar magnet c. Electromagnet d. Horseshoe magnet
Last Answer : b.Bar magne
Description : The induced emf is produced in a circuit due to: a. Initial magnetic flux b. final magnetic flux c. Change of magnetic flux d. constant magnetic flux
Last Answer : d. constant magnetic flux
Description : Which of the following does not equal the unit of magnetic flux density? a) 1 Wbm-2 b) 1 NA-1m -1 c) Both (a) and (b) d) 1 Wbm-1
Last Answer : d) 1 Wbm-1
Description : Tesla is a unit of (a) field strength (b) inductance (c) flux density (d) flux
Last Answer : (c) flux density
Description : A particle is projected in a plane perpendicular to a uniform magnetic field. The area bounded by the path described by the particle is proportional t
Last Answer : A particle is projected in a plane perpendicular to a uniform magnetic field. The area bounded by the ... C. the kinetic energy D. None of these
Description : Force on a moving charge in a uniform magnetic field depends uponA. magnetic flux density B. the charge on the particle C. the speed of particle D. all of above
Last Answer : all of above
Description : An electron is travelling at right angles to a uniform magnetic field of flux density 1.2 mT with a speed of 8 × 106 m s-1, the radius of circular path followed by electron is A. 3.8 cm B. 3.7 cm C. 3.6 cm D. 3.5 cm
Last Answer : 3.8 cm
Description : The induced emf in a coil depends upon: a. Strength of magnetic field b. Resistance of the coil c. area of the coil d. All of them
Last Answer : d. All of them
Description : A conductor of length L has current I passing through it, when it is placed parallel to a magnetic field. The force experienced by the conductor will be (a) zero (b) BLI (c) B2LI (d) BLI2
Last Answer : (a) zero
Description : When an iron piece is placed in a magnetic field (a) the magnetic lines of force will bend away from their usual paths in order to go away from the piece (b) the magnetic lines of force will bend ... to pass through the piece (c) the magnetic field will not be affected (d) the iron piece will break
Last Answer : (b) the magnetic lines of force will bend away from their usual paths in order to pass through the piece
Description : If velocity of a conductor moving through a magnetic field ‘B’ is made zero, then Motional emf will be: a. –VBL b. –V/BL c. – BL/V d. zero
Last Answer : a. –VBL
Description : The circuit which changes input signal at output with phase shift of 1800 is called (a) Amplifier (b) operational amplifier (c) switch (d) inverter
Last Answer : (d) inverter
Description : Indicatewhich ofthe followingfrequencies cannotbe used forreliablebeyond-the-horizon terrestrial communicationswithoutrepeaters: a. 20 kHz b. 15 MHz c. 900 MHz d. 12GHz
Last Answer : d. 12GHz
Description : A metallic hallow sphere of 8cm diameter is charged with 4 × 10−8c. The potential on its surface will be: (a) 90 volts (b) 9 volts (c) 9000 volts (d) 900 volts
Last Answer : c) 9000 volts
Description : A wire of uniform area of cross-section A length L and resistance R is cut into two parts. Resistivity of each part a. remains the same b. is doubled c. is halved d. becomes zero
Last Answer : a. remains the same
Description : A proton of mass m and charge q is moving in a plane with kinetic energy E. if there exists a uniform magnetic field B, perpendicular to the plane mot
Last Answer : A proton of mass m and charge q is moving in a plane with kinetic energy E. if there exists a uniform magnetic ... Em))/(2qB)` D. `(sqrt(2Eq))/(qB)`
Description : A conducting loop is placed in a uniform magnetic field with its plane perpendicular to the field with its plane perpendicular to the field. An emf is
Last Answer : A conducting loop is placed in a uniform magnetic field with its plane perpendicular to the field ... . the loop is deformed from the original shape
Description : Assertion A charged particle is rotating in a circular path in uniform magnetic field. Then, plane of circle is perpendicular to the magnetic field. R
Last Answer : Assertion A charged particle is rotating in a circular path in uniform magnetic field. Then, plane of ... . If Assertion is false but Reason is true.
Description : A circular loop of mass m and radius r in X-Y plane of a horizontal table as shown in figure. A uniform magnetic field B is applied parallel to X-axis
Last Answer : A circular loop of mass m and radius r in X-Y plane of a horizontal table as shown in figure. A uniform ... . `(mg)/(2pirB)` D. `(pirB)/(mgl)`
Description : If a charged particle is a plane perpendicular to a uniform magnetic field with a time period T Then
Last Answer : If a charged particle is a plane perpendicular to a uniform magnetic field with a time period T Then A. `T^(2) ... ` C. `Tpropr^(2)` D. `Tpropr^(0)`
Description : A conducting loop carrying a current `I` is placed in a uniform magnetic field ponting into the plane of the paper as shown. The loop will have a tend
Last Answer : A conducting loop carrying a current `I` is placed in a uniform magnetic field ponting into the plane of the ... +ve X-axis D. move towards -ve X-axis
Description : The left hand rule correlates to (a) current, induced e.m.f. and direction of force on a conductor (b) magnetic field, electric field and direction of force on a conductor (c) self induction, ... and direction of force on a conductor (d) current, magnetic field and direction of force on a conductor
Last Answer : (d) current, magnetic field and direction of force on a conductor
Description : A material which is slightly repelled by a magnetic field is known as (a) ferromagnetic material (b) diamagnetic material (c) paramagnetic material (d) conducting material
Last Answer : (b) diamagnetic material
Description : A magnetic field exists around (a) iron (b) copper (c) aluminium (d) moving charges
Last Answer : (d) moving charges
Description : The windings of the electromagnetic are usually called: a. Magnetic coils b. Field coil c. Electric coil d. simple coil
Last Answer : c. Electric coil
Description : The induced current can be increased by: a. Using strong magnetic field b. moving loop faster c. Replacing loop by coil d. all of above
Last Answer : d. all of above