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 most common type of AC service generator found aboard ship is the stationary _____________. A. electromagnetic field, revolving armature type B. electromagnetic field, oscillatory armature type C. armature, oscillatory electromagnet field type D. armature, rotating electromagnetic field type
Last Answer : Answer: D
Description : An electrical device which employs a stationary armature and a rotating electromagnetic field is used aboard ship as a ____________. A. magnetic amplifier B. ship's service alternator C. three-wire DC generator D. saturable core reactor
Last Answer : Answer: B
Description : What Are The Advantages Of Stationary Armature And Rotating Field System?
Last Answer : The stationary armature coils can be insulated easily. Higher peripheral speed can be achieved in the rotor. Cooling of the winding is more efficient. Only two slip rings are required to give DC ... Output current can be easily supplied to the load circuit. Slip-rings and brushes are not necessary.
Description : In a d.c. machine, the armature mmf is (A) stationary w.r.t. armature. (B) rotating w.r.t. field. (C) stationary w.r.t. field. (D) rotating w.r.t. brushes.
Last Answer : (C) stationary w.r.t. field.
Description : According to Bohr’s theory, the fourth stationary orbit of electrons in the hydrogen atom is a) 4 (0.053 nm) b) 9 (0.053 nm) c) 16 (0.053 nm) d) 25(0.053 nm)
Last Answer : c) 16 (0.053 nm)
Description : For Hydrogen atom, the allowed stationary orbits are those whose orbital angular momentum is equal to an integral multiple of h i.e., mvr = a) nh/2π b) nh x 2π c) nh / 2λ d) nh / 2πλ
Last Answer : a) nh/2π
Description : The electrons in the outermost orbit of atom are: a) Valance electrons b) Static electrons c) Tightly bound d) Stationary
Last Answer : a) Valance electrons
Description : Does this microwave have a rotating plate inside or is it stationary?
Last Answer : This microwave has a 12 5/8 in. rotating turntable inside.
Description : Will The Alternators Have Rotating Armature System Or Stationary Armature System?
Last Answer : Generally in alternators, the armature is stationary and the field rotates. Small low-voltage alternators often have a rotating armature and a stationary field winding. But in large alternators rotating armature field type is used.
Description : The static load is defined as the load acting on the bearing when the shaft is _____. (a) stationary (b) rotating at rpm
Last Answer : (a) stationary
Description : Static load is defined as the load acting on the bearing when shaft is _____ a) Stationary b) Rotating at rpm
Last Answer : a) Stationary
Description : Is it necessary for an axle to be ______ with respect to rotating element? a) Stationary b) Moving c) Moving or stationary d) None of the listed
Last Answer : c) Moving or stationary
Description : Is it necessary for an axle to be ______ with respect to rotating element? a) Stationary b) Moving c) Moving or stationary d) fixed
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 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 : 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 : 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 : 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 : 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 : A magnetic field exists around (a) iron (b) copper (c) aluminium (d) moving charges
Last Answer : (d) moving charges
Description : Tesla is a unit of (a) field strength (b) inductance (c) flux density (d) flux
Last Answer : (c) flux density
Description : Themechanicalsplice isbestsuited for a. quicker installation under ideal conditions b. minimum attenuation losses c. field service conditions d. situations in which cost of equipment is not a factor
Last Answer : c. field service conditions
Description : Laser technology has been widely used in the field of a) neurology b) astrology c) ophthalmology d) psychology
Last Answer : c) ophthalmology
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 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 : 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 : 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 motor a permanent magnet provides: a. Electric field b. electric flux c. magnetic field d. gravitational field
Last Answer : d. gravitational field
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 : A magnetic field acts on a charged particles so as to change its: a. speed b. energy c. direction of motion d. all of these
Last Answer : Only direction of motion will change ...it means velocity will change but speed same
Description : If magnetic field is doubled then magnetic energy density becomes: a. Four times b. Two times c. Three times d. Six times
Last Answer : c. Three times
Description : Electric current produces magnetic field was suggested by: a. Faraday b. Lenz c. Ohm d. Oerested
Last Answer : c. Ohm
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 : 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 : 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 proton and a deuteron have same kinetic energies while moving in a perpendicular magnetic field. The following gives the ratio of radii of their circular paths a) √2 : 1 b) 1: √2 c) 1:4 d) 1:1
Last Answer : b) 1: √2
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 : An α particle moves perpendicular to a constant magnetic field of strength 1.2 T in a circular path of radius 0.7 m. The speed of α particle in ms-1 is ______________ a) 2.7 × 107 b) 2.6 × 107 c) 3.2 × 107 d) 2.0 × 107
Last Answer : a) 2.7 × 107
Description : A solenoid has n turns and length l. If length is reduced to l/2 and turns are doubled then magnetic field B produced by it becomes equal to a) 2B b) 4B c) 1/2 B d) None of these
Last Answer : a) 2B
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 : 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 proton having mass m and charge q is projected into a region having a perpendicular magnetic field. The angle of deviation of proton when it comes out of the region with mv √2 qB ⁄ is a) π/3 b) π/4 c) π/6 d) 2 π/3
Last Answer : b) π/4
Description : ___________ remain undeflected in a magnetic field a) β particles b) α particles c) γ rays d) Proton beams
Last Answer : c) γ rays
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 : 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