The torque, in a DC series motor is proportional to the square of the armature current.
Description : The torque, in a _____________is proportional to the square of the armature current (A) DC shunt motor (B) stepper motor (C) 2-phase servomotor (D) DC series motor
Last Answer : (D) DC series motor
Last Answer : The armature torque of the D.C. shunt motor is proportional to armature current.
Description : An increase in the amount of current flow through the armature of a shunt motor is the final result of a/an _____________. A. increase in the load on the motor B. decrease in the load on the motor C. increase in counter EMF D. decrease in armature torque
Last Answer : Answer: A
Description : The amount of mechanical force or torque produced by an electric motor depends on the ________________. A. strength of its magnetic field B. amount of armature current flow C. length of conductor in the field D. all of the above
Last Answer : Answer: D
Description : A dc cumulatively compounded motor delivers rated load torque at rated speed. If series field is short circuited, then the armature current and speed will a) Both increases b) Both decreases c) Increases and decreases d) Decreases and increases
Last Answer : Ans: Both increases
Description : As compared to shunt and compound DC motors, the series DC motor will have the highest torque because of its comparatively ____________ at the start. (A) Lower armature resistance. (B) Stronger series field. (C) Fewer series turns. (D) Larger armature current.
Last Answer : (D) Larger armature current.
Description : If the current in the armature of do series motor is reduced to 5%, the torque of the motor will become: (1) 50% of the previous value (2) 25% of the previous value (3) 150% of the previous value (4) 125% of the previous value
Last Answer : If the current in the armature of do series motor is reduced to 5%, the torque of the motor will become: 25% of the previous value
Description : A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A. The torque produced when the armature current is 20 A, is?
Last Answer : Armature torque, Ta=PØZIa/2πA So Ta1/Ta2=Ia1/Ia2 Ta2=Ta1*Ia2/Ia1 =54*20/10 =108
Last Answer : In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 25% of the previous value.
Last Answer : The current drawn by the armature of D.C. motor is directly proportional to the torque required.
Description : A_______ bearing supports the load acting along the axis of the shaft. a) Thrust b) Radial c) Longitudinal d) Transversal
Last Answer : a) Thrust
Description : A local telephone network isan example of a_______ network. A) packet-switched B) circuit-switched C) message-switched D) none of the above
Last Answer : circuit-switched
Description : A one-to-all communication between one source and all hosts on a network is classified as a_______ communication. A) unicast B) multicast C) broadcast D) none of the above
Last Answer : broadcast
Description : A syllogism in which the major premise is a hypothetical proposition, the minor and the conclusion are categorical propositions is a_______. A) Categorical syllogism B) Hypothetical syllogism C) Disjunctive syllogism D) Dilemma.
Last Answer : B) Hypothetical syllogism
Description : The torque produced by a DC motor armature is the product of the force acting at the armature surface multiplied by _____________. A. work done by the armature in one revolution B. effective ... arm at the center of rotation of the armature D. perpendicular distance to its center of rotation
Description : Reduction in the capacitance of a capacitor-start motor, results in reduced (A) Noise. (B) Speed. (C) Starting torque. (D) Armature reaction.
Last Answer : Ans: C Reduction in the capacitance reduces starting voltage, which results in reduced starting torque.
Description : The introduction of interpoles in between the main pole improves the performance of d.c. machines, because (A) The interpole produces additional flux to augment the developed torque. (B) The flux waveform is ... armature is removed. (D) A counter e.m.f. is induced in the coil undergoing commutation.
Last Answer : Ans: D Counter e.m.f is produced, it neutralizes the reactive emf.
Description : The shaft torque of a d.c. motor is less than its armature torque because of .......... losses.
Last Answer : The shaft torque of a d.c. motor is less than its armature torque because of rotational losses.
Description : The no load speed of a d.c. shunt motor is 1140 rpm. At full load, the armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full load speed in rpm will be: (A) 1080 (B) 1203 (C) 1000 (D) 1200
Last Answer : The no load speed of a d.c. shunt motor is 1140 rpm. At full load, the armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full load speed in rpm will be: 1080
Description : In DC generators, armature reaction is produced by the: (A) field current (B) armature conductors (C) field pole winding (D) load current in armature
Last Answer : In DC generators, armature reaction is produced by the: load current in armature
Description : If the phase -angle of the voltage coil of a directional relay is 50°, the maximum torque angle of the relay is: (A) 130° (B) 100° (C) 50° (D) 25°
Last Answer : If the phase -angle of the voltage coil of a directional relay is 50°, the maximum torque angle of the relay is: 50°
Description : In a shaft shear stress intensity at a point is not (A) Directly proportional to the distance from the axis (B) Inversely proportional to the distance from the axis (C) Inversely proportional to the polar moment of inertia (D) Directly proportional to the applied torque
Last Answer : (B) Inversely proportional to the distance from the axis
Description : The torque produced in wattmeter is proportional to
Last Answer : A
Last Answer : In a moving iron meter, the deflecting torque is proportional to Square of the current through the coil.
Last Answer : In a moving coil instrument, the deflecting torque is proportional to Current.
Last Answer : In a ballistic galvanometer, the deflecting torque is proportional to the current through coil.
Last Answer : In the case of PMMC rectifier type instruments, the deflecting torque is proportional to Average value of AC current.
Description : Eddy current loss is proportional to the (A) frequency. (B) square of the frequency. (C) cube of the frequency. (D) square-root of the frequency.
Last Answer : (B) square of the frequency.
Description : The periodic time of a body moving in Simple Harmonic Motion is a.Directly proportional to its angular velocity b.Directly proportional to the weight of the body c.Inversely proportional to ... d.Directly proportional to the momentum of swinging body e.Inversely proportional to the angular velocity
Last Answer : e. Inversely proportional to the angular velocity
Description : Let the only force acting on two bodies be their mutual interactions. If both bodies start from rest, the distances travelled by each will be a a.proportional to the respective masses of the ... masses of the bodies e.inversely proportional to the square of the respective masses of the bodies
Last Answer : c. inversely proportional to the respective masses of the bodies
Description : According to Kepler's law of motion the square of the time period T of a planet around the sun is proportional to the a.mean distance b.square of the mean distance of planet from sun c.cube of the mean distance of planet from sun d.107 dynes e.3/2 power of the mean distance
Last Answer : c. cube of the mean distance of planet from sun
Description : The velocity of sound is ….. the density of the medium. (a) Directly proportional to (b) Inversely proportional to (c) Directly proportional to the square root of (d) Inversely proportional to the square root of
Last Answer : Ans:(d)
Description : The frequency of vibration of a stretched string is _______ its length. (a) Directly proportional to (b) Inversely proportional to (c) Directly proportional to the square of (d) Independent of
Last Answer : Ans:(b)
Description : Kepler's law of planetary motion states that the square of the time period is proportional to the – (1) semi-major axis (2) square of the semi-major axis (3) cube of the semi-major axis (4) fourth power of the serni-major axis
Last Answer : (3) cube of the semi-major axis Explanation: Kepler's law of planetary motion states that the square of the time period is proportional to the cube of the semi-major axis.
Description : An object covers distance which is directly proportional to the square of the time. Its acceleration is – (1) increasing (2) decreasing (3) zero (4) constant
Last Answer : (4) constant Explanation: When an object covers distance which is directly proportional to the square of the time, its acceleration is constant. This is seen in the cases of falling objects. This connection between time and distance was first observed by Galileo.
Description : Intensity of any wave is proportional to which of the following? (1) Amplitude (2) Square of amplitude (3) Square root of amplitude (4) Cube of amplitude
Last Answer : (2) Square of amplitude Explanation: The energy of a wave is proportional to the square of its amplitude. Therefore, the intensity of a wave is also proportional to the square of its amplitude.
Description : The square of the thermal noise voltage generated by a resistor is proportional to A. its resistance B. its temperature C. the bandwidth over which it is measured D. All of the above
Last Answer : D. All of the above
Description : During agitation of liquids, power consumption during laminar flow is not proportional to the (A) Density of the liquid (B) Viscosity of the liquid (C) Cube of impeller diameters (D) Square of rotational speed
Last Answer : (A) Density of the liquid
Description : Rittinger's crushing law states that (A) Work required to form a particle of any size is proportional to the square of the surface to volume ratio of the product (B) Work required to form a ... ) For a given machine and feed, crushing efficiency is dependent on the size of the feed & product
Last Answer : (C) Work required in crushing is proportional to the new surface created
Description : Bond crushing law (A) Calls for relatively less energy for the smaller product particles, than does the Rittinger law (B) Is less realistic in estimating the power requirements of commercial crushers ( ... (D) States that the work required for the crushing is proportional to the new surface created
Last Answer : (A) Calls for relatively less energy for the smaller product particles, than does the Rittinger law
Description : Boyle's law states that A. pressure of a gas is inversely proportional to its volume i.e. P V = constant B. pressure of a gas is directly proportional to its volume i.e. P⁄V = constant C. ... of a gas is directly proportional to the square of its volume i.e. P ⁄ V² = constant
Last Answer : pressure of a gas is inversely proportional to its volume i.e. P × V = constant
Description : Assuming uniform density of the core, the acceleration due to gravity below the Earth's surface is A. inversely proportional to the square of the distance from the center of the Earth ... center of the Earth D. directly proportional to the distance from the center of the Earth
Last Answer : directly proportional to the distance from the center of the Earth
Description : Square of orbital period is proportional to A. radius B. square of radius C. cube of radius D. square of diameter
Last Answer : cube of radius
Description : When two concentric springs are made of same material, having same free length and compressed equally by axial load, then the load shared by each spring is proportional to (A) Spring index of each spring ... spring (C) Mean coil diameter of each spring (D) Square of wire diameter of each spring
Last Answer : (D) Square of wire diameter of each spring
Description : The load shared by each spring is inversely proportional to the cross section of wire. a) Yes b) No, it is directly proportional c) It is proportional to its square d) It is proportional to its square root
Last Answer : b) No, it is directly proportional
Description : According to Newton's law of universal gravitation, any two particles of finite mass attract one another with a force which is A. Inversely proportional to the product of their masses and ... the product of their masses and inversely proportional to the square of their distance apart
Last Answer : Directly proportional to the product of their masses and inversely proportional to the square of their distance apart
Description : Electrical force exerted by two point charges on each other is inversely proportional to A. sum of their charges B. product of their charges C. distance between them D. square of distance between them
Last Answer : square of distance between them
Description : Solid angle subtended by the finite surface at the radiating element is (A) Called the view factor (B) Called the angle of vision (C) Proportional to the square of the distance between surfaces (D) Expressed in terms of radians
Last Answer : (B) Called the angle of vision
Description : Which of the following statements are TRUE for damped vibrations? (P) . For a system having critical damping, the value of the damping ratio is unity and system does not undergo a vibratory motion. (Q) . Logarithmic decrement method ... Q only (B) P and S only (C) P, Q and R only (D) Q and S only
Last Answer : (C) P, Q and R only
Description : In a heat exchanger, the rate of heat transfer from the hot fluid to the cold fluid (A) Varies directly as the area and the LMTD (B) Directly proportional to LMTD and inversely proportional to the area (C) Varies as square of the area (D) None of these
Last Answer : (A) Varies directly as the area and the LMTD