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 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 : 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 : The greatest induced EMF will occur in a straight wire moving at constant speed through a uniform magnetic field when the angle between the direction of the wire's motion and the direction of the magnetic field is w) 0 degrees x) 30 degrees y) 60 degrees z) 90 degrees
Last Answer : ANSWER: Z -- 90 DEGREES
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 : 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 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
Description : Assertion A flexeble wire loop of irregular shape carrying current when placed in a uniform external magnetic field acquires a circular shape. Reason
Last Answer : Assertion A flexeble wire loop of irregular shape carrying current when placed in a uniform external ... circular shape is having the greatert area.
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 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 : 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 : 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 : The magnetic field is _________ inside a solenoid a) Zero b) uniform c) non-uniform d) infinite
Last Answer : b) uniform
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 : 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 : 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 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 : The magnetic flux φB through a plane element of area A⃗ in a uniform magnetic field B⃗⃗ is minimum at a) θ = 900 b) θ = 00 c) θ = 1800 d) None of these
Last Answer : a) θ = 900
Description : In the figure shown, a conducting wire PQ of length l=1m, is moved in a uniform magnetic field B=4T with constant velocity v=2m/s towards right. Given
Last Answer : In the figure shown, a conducting wire PQ of length l=1m, is moved in a uniform magnetic field B=4T with ... P_(2) = 32 J//s` D. None of these
Last Answer : In the figure shown, a conducting wire PQ of length l=1m, is moved in a uniform magnetic field B=4T with constant ... `16 N` C. `24 N` D. `32 N`
Last Answer : In the figure shown, a conducting wire PQ of length l=1m, is moved in a uniform magnetic field B=4T with constant ... `0` B. `2A` C. `4A` D. `6A`
Description : The direction of induced EMF can be found with the help of -
Last Answer : Lenz’s Law
Description : The phenomena of induced emf was observed by Faraday and Henry in: a. 1931 b. 1831 c. 1535 d. 1940
Last Answer : a. 1931
Description : A circular flexible loop of wire of radius r carrying a current I is placed in a uniform magnetic field B . If B is doubled, then tension in the loop
Last Answer : A circular flexible loop of wire of radius r carrying a current I is placed in a uniform magnetic field ... is doubled C. is halved D. becomes 4 times
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 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 : Resistance of an ideal insulator is a. Infinite b. Zero c. Finite d. depends upon nature
Last Answer : a. Infinite
Description : Assertion Net torque in the current carrying loop placed in a uniform magnetic field (pointing inwards) is zero. Reasonl Magnetic moment (M) is inward
Last Answer : Assertion Net torque in the current carrying loop placed in a uniform magnetic field (pointing inwards) ... . Reasonl Magnetic moment (M) is inwards.
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 : 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 : 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 : When a motor is just started, back emf is almost ______: a. Infinite b. zero c. minimum d. maximum
Last Answer : d. maximum
Description : If the motor is overloaded, then the magnitude of ‘back emf’” a. Increases b. Decreases c. Constant d. Becomes zero
Last Answer : Increases
Description : Terminal potential difference of a battery is greater than its emf when a. the internal resistance of battery is infinite b. the internal resistance of battery is zero c. the battery is charged d. the battery is discharged
Last Answer : c. the battery is charged
Description : A charged particle is moving in a UNIFORM magnetic field. If the direction of motion of the charged particle is parallel to the magnetic field, describe the shape of the charged particle's path.
Last Answer : ANSWER: STRAIGHT LINE
Description : When the field is strong, the lines of force are: (a) Closer (b) Parallel (c) Farther (d) All of above 45. The electric lines of force determine the strength of an: (a) Gravitational field (b) Constant field (c) Magnetic field (d) Electric field
Last Answer : d) Electric field
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 : For a straight wire, induced current depends uponA. the speed of movement of wire B. the length of wire C. the magnitude of magnetic flux density D. all of above
Last Answer : all of above
Description : Resistance of a wire on increasing its temperature will a. increase with rise in temperature b. decrease with rise in temperature c. will remain same d. depends upon altitude of experimentation
Last Answer : a. increase with rise in temperature
Description : A conductor of length 5 cm is moved paralllel to itself with a speed of `2m//s`, perpendicular to a uniform magnetic field of `10^(-3) Wb//m^(2).` the
Last Answer : A conductor of length 5 cm is moved paralllel to itself with a speed of `2m//s`, perpendicular to a uniform ... `1xx10^(-4)V` D. `2xx10^(-4) V`
Description : A current carrying loop is placed in a uniform magnetic field. The torque acting on it does not depend upon
Last Answer : A current carrying loop is placed in a uniform magnetic field. The torque acting on it does not ... turns in the loop D. strength of the current
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 : To couple a coaxialline toa parallel-wire line,itisbesttouse a a. slotted line b.balun c. directional coupler d. quarter-wave transformer
Last Answer : b.balun
Description : All electrical appliances are connected in parallel to each other between the main line and neutral wire to get a. same current b. same current and potential difference c. different current but same potential difference d. different current and potential differences
Last Answer : c. different current but same potential difference
Description : Two electron beams move parallel to each other. The nature of force between them is a) Attractive b) Repulsive c) Dependent on magnitude of velocity d) None
Last Answer : b) Repulsive
Description : Materials subjected to rapid reversal of magnetism should have (a) large area oiB-H loop (b) high permeability and low hysteresis loss (c) high co-ercivity and high retentivity (d) high co-ercivity and low density
Last Answer : (b) high permeability and low hysteresis loss
Description : A straight wire of length 0.20 m moves at a steady speed of 3.0 m s-1 at right angles to the magnetic field of flux density 0.10 T. The e.m.f induced across ends of wire is A. 0.5 V B. 0.06 V C. 0.05 V D. 0.04 V
Last Answer : 0.06 V
Description : 1. Consider a circular loop of wire lying in the plane of the table. Let the current pass through the loop clockwise. Apply the right-hand rule to find out the direction of the magnetic field inside and outside the loop. -Physics-10
Last Answer : Solution: For the downward direction of the current, the direction of the magnetic field will be as if emerging from the table outside the loop and merging with the table inside the loop. Similarly, ... the table outside the loop and merging with the table inside the loop, as shown in the figure.