The coefficient of coupling between two coils is 0.45. The first coil has an inductance of 75 mH and the second...

The coefficient of coupling between two coils is 0.45. The first coil has an inductance of 75 mH and the second coil has an inductance of 105 mH. What is the mutual inductance between the coils? 

(1) 3.54 mH (2) 7.88 mH (3) 39.9 mH (4) 189.3 mH
by

1 Answer

Answer :

The coefficient of coupling between two coils is 0.45. The first coil has an inductance of 75 mH and the second coil has an inductance of 105 mH. 39.9 mH is the mutual inductance between the coils.

by

Related questions

Two similar coils have self inductance of 1 mH each. Coefficient of ...

Description : Two similar coils have self inductance of 1 mH each. Coefficient of coupling is 0.5. The mutual inductance M is

Last Answer : Two similar coils have self inductance of 1 mH each. Coefficient of coupling is 0.5. The mutual inductance M is 0.5 mH.

Two coils in differential connection have self-inductance of 2 mH and 4 ...

Description : Two coils in differential connection have self-inductance of 2 mH and 4 mH and a mutual inductance of 0.15 mH. The equivalent inductance of the combination is

Last Answer : Two coils in differential connection have self-inductance of 2 mH and 4 mH and a mutual inductance of 0.15 mH. The equivalent inductance of the combination is 5.7 mH.

A coil of inductance 240 mH and resistance 75 Ohm is connected in parallel with a capacitor across a 30 V,

Description : A coil of inductance 240 mH and resistance 75 Ohm is connected in parallel with a capacitor across a 30 V, variable frequency supply. The current drawn by the circuit is found to be minimum when the supply frequency is 1 kHz. The ... (A) 40, 400 Hz (B) 10, 100 Hz (C) 20, 50 Hz (D) 50, 20 Hz

Last Answer : A coil of inductance 240 mH and resistance 75 Ohm is connected in parallel with a capacitor across a 30 V, variable frequency supply. The current drawn by the circuit is found to be minimum ... supply frequency is 1 kHz. The approximate values of Q-factor and bandwidth are, respectively 20, 50 Hz

A 100 turn coil has an inductance of 6 mH. If the number of turns is increased to 200, all other quantities

Description : A 100 turn coil has an inductance of 6 mH. If the number of turns is increased to 200, all other quantities remaining the same, the inductance will be:

Last Answer : A 100 turn coil has an inductance of 6 mH. If the number of turns is increased to 200, all other quantities remaining the same, the inductance will be: 24 mH

Two coils have a mutual inductance 0.005H. The current changes in the first coil according to the equation `I=I_(0) sin omegat "where" I_(0)=10A and o

Description : Two coils have a mutual inductance 0.005H. The current changes in the first coil according to the equation `I=I_(0) sin omegat "where" I_(0)=10A and o

Last Answer : Two coils have a mutual inductance 0.005H. The current changes in the first coil according to the equation `I ... (pi//x)` volts. Find the value of x.

The current in a 200 mH coil increases from 2 to 5 A in 0.1 Second. What is rate of change of current?

Description : The current in a 200 mH coil increases from 2 to 5 A in 0.1 Second. What is rate of change of current? A. 30 A/s B. 20 A/s C. 10 A/s D. none of these

Last Answer : The current in a 200 mH coil increases from 2 to 5 A in 0.1 Second. 30 A/s is rate of change of current.

The coefficient of coupling between two air core coils depends on

Description : The coefficient of coupling between two air core coils depends on   (A) mutual inductance between two coils only (B) self inductances of the two coils only (C) mutual inductance and self inductances of the two coils (D) none

Last Answer : The coefficient of coupling between two air core coils depends on mutual inductance and self inductances of the two coils 

The co-efficient of coupling of two coils depends on

Last Answer : The co-efficient of coupling of two coils depends on Physical location of the coils.

A 800 kV transmission line is having per phase line inductance of 1.1 mH/km and per phase line capacitance

Description : A 800 kV transmission line is having per phase line inductance of 1.1 mH/km and per phase line capacitance of 11.68 nF/km. Ignoring the length of the line, its ideal power transfer capability in MW is (A) 1204 MW (B) 1504 MW (C) 2085 MW (D) 2606 MW

Last Answer : A 800 kV transmission line is having per phase line inductance of 1.1 mH/km and per phase line capacitance of 11.68 nF/km. Ignoring the length of the line, its ideal power transfer capability in MW is 2085 MW

On doubling the number of turns of a coil the inductance

Last Answer : On doubling the number of turns of a coil the inductance Quadruples.

The coefficient of venturi-flume, generally, lies between (A) 0.3 to 0.45 (B) 0.50 to 0.75 (C) 0.75 to 0.95 (D) 0.95 to 1.0

Description : The coefficient of venturi-flume, generally, lies between (A) 0.3 to 0.45 (B) 0.50 to 0.75 (C) 0.75 to 0.95 (D) 0.95 to 1.0

Last Answer : Answer: Option D

Calculate the mutual inductance of two tightly coupled coils with inductances 49H and 9H. a) 21 b) 58 c) 40 d) 49/9

Description : Calculate the mutual inductance of two tightly coupled coils with inductances 49H and 9H. a) 21 b) 58 c) 40 d) 49/9

Last Answer : a) 21

The equivalent inductance of two coils with series opposing flux having inductances 7H and 2H with a mutual inductance of 1H. a) 10 b) 7 c) 11 d) 13

Description : The equivalent inductance of two coils with series opposing flux having inductances 7H and 2H with a mutual inductance of 1H. a) 10 b) 7 c) 11 d) 13

Last Answer : b) 7

The equivalent inductances of two coils 2H and 5H in series aiding flux with mutual inductance of 3H is a) 10 b) 30 c) 1 d) 13

Description : The equivalent inductances of two coils 2H and 5H in series aiding flux with mutual inductance of 3H is a) 10 b) 30 c) 1 d) 13

Last Answer : d) 13

Inductance coils are basically designed for

Last Answer : Inductance coils are basically designed for High Q.

An AC circuit consists of a resistance and a choke coil in series . The resistance is of 220 `Omega` and choke coils is of 0.7 H . The power abosorbed

Description : An AC circuit consists of a resistance and a choke coil in series . The resistance is of 220 `Omega` and choke coils is of 0.7 H . The power abosorbed

Last Answer : An AC circuit consists of a resistance and a choke coil in series . The resistance is of 220 ` ... 50 Hz , source connected with the circuit , is

If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the diameter of each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m. Permissible tensile stress is 80N/mm2. a) 27mm b) 25mm c) 23mm d) 21mm

Description : If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the diameter of each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m. Permissible tensile stress is 80N/mm2. a) 27mm b) 25mm c) 23mm d) 21mm

Last Answer : a) 27mm

If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the tensile force on each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m. a) 51234.4N b) 45968.3N c) 41666.7N d) None of the listed

Description : If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the tensile force on each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m. a) 51234.4N b) 45968.3N c) 41666.7N d) None of the listed

Last Answer : c) 41666.7N

A coil =of inductance `L=50muH` and resistance =`0.5Omega` is connected to a battery of emf=5A. A resistance of `10Omega` is connected parallel to the

Description : A coil =of inductance `L=50muH` and resistance =`0.5Omega` is connected to a battery of emf=5A. A resistance of `10Omega` is connected parallel to the

Last Answer : A coil =of inductance `L=50muH` and resistance =`0.5Omega` is connected to a battery of emf=5A. A resistance ... is (0.02)x in mJ. Find valuie of x.

A transmitted signal 5 meters in wavelength is received by an antenna coil having a 50-Ω resistance and a 0.01 H inductance. What is the capacitance of the tuner shunting the antenna coil at this point? A. 0.704 fF B. 0.704 μF C. 0.704 nF D. 0.704 mF

Description : A transmitted signal 5 meters in wavelength is received by an antenna coil having a 50-Ω resistance and a 0.01 H inductance. What is the capacitance of the tuner shunting the antenna coil at this point? A. 0.704 fF B. 0.704 μF C. 0.704 nF D. 0.704 mF

Last Answer : A. 0.704 fF

Two circular coils 1 and 2 are made from the same wire but the radius of the 1st coil is twice that of the 2nd coil. What is the ratio of potentail di

Description : Two circular coils 1 and 2 are made from the same wire but the radius of the 1st coil is twice that of the 2nd coil. What is the ratio of potentail di

Last Answer : Two circular coils 1 and 2 are made from the same wire but the radius of the 1st coil is twice that of the 2nd coil ... the same? A. 3 B. 4 C. 6 D. 2

If two coils are wound on a single iron core, what will a change in current in one coil cause in the other coil?

Description : If two coils are wound on a single iron core, what will a change in current in one coil cause in the other coil?

Last Answer : A change in inductance.

The distance between the starts of two consecutive coils measured in terms of coil sides is called (a) front pitch (b) winding pitch (c) commutator pitch (d) back pitch

Description : The distance between the starts of two consecutive coils measured in terms of coil sides is called (a) front pitch (b) winding pitch (c) commutator pitch (d) back pitch

Last Answer : (b) winding pitch

Air gap readings should be taken periodicly on electrical generation equipment to __________. A. determine the amount of varnish that can be applied to correct insulation problems B. determine the condition of the bearings C. provide for the correct proper tightening of the field coil bolts and correct lateral adjustment of the field coils D. increase machine efficiency

Description : Air gap readings should be taken periodicly on electrical generation equipment to __________. A. determine the amount of varnish that can be applied to correct insulation problems B. determine the ... field coil bolts and correct lateral adjustment of the field coils D. increase machine efficiency

Last Answer : Answer: B

When troubleshooting motor controllers, a shorted relay or contactor coil is often indicated by _______________. A. a resistance reading of 'infinity' on an ohmmeter B. charred insulation and/or a blown control fuse C. a reading of 'zero' on a megger from one of the coil's leads to ground D. a higher-than-normal voltage reading across the winding

Description : When troubleshooting motor controllers, a shorted relay or contactor coil is often indicated by _______________. A. a resistance reading of 'infinity' on an ohmmeter B. charred insulation and/or a blown ... of the coil's leads to ground D. a higher-than-normal voltage reading across the winding

Last Answer : Answer: B

Excessive humming of AC contactors may be caused by ______________. A. burnt arc shields B. shorted armature coils C. a broken shading coil D. high voltage

Description : Excessive humming of AC contactors may be caused by ______________. A. burnt arc shields B. shorted armature coils C. a broken shading coil D. high voltage

Last Answer : Answer: C

If coil 'R1-R2' on the transmitter in figure 'A' shown in the illustration is turned 30 degrees clockwise, corresponding coil 'R1-R2' on the receiver should ____________. EL-0092 A. make coils 'S1-S2-S3' turn faster because of induced currents B. ring at the receiving station until the turning stops C. receive a higher voltage depending on the turns ratio D. align itself to the same position if free to move

Description : If coil 'R1-R2' on the transmitter in figure 'A' shown in the illustration is turned 30 degrees clockwise, corresponding coil 'R1-R2' on the receiver should ____________. EL-0092 A. make coils 'S1 ... a higher voltage depending on the turns ratio D. align itself to the same position if free to move

Last Answer : Answer: D

Shading coils are installed on AC full-voltage starters to _____________. A. eliminate contact chatter B. dissipate opening contact arcs C. delay current build up in the holding coil D. protect the motor windings from momentary starting current overload

Description : Shading coils are installed on AC full-voltage starters to _____________. A. eliminate contact chatter B. dissipate opening contact arcs C. delay current build up in the holding coil D. protect the motor windings from momentary starting current overload

Last Answer : Answer: A

A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an equal or lower value B. low or zero voltage reading, while the other coils will have higher readings C. fluctuating voltmeter reading, while the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating

Description : A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an ... the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating

Last Answer : Answer: B

The maximum shear stress in spring wire is induced at (A) Inner surface of the coil (B) Outer surface of the coil (C) Central surface of the coil (D) End coils

Description : The maximum shear stress in spring wire is induced at (A) Inner surface of the coil (B) Outer surface of the coil (C) Central surface of the coil (D) End coils

Last Answer : (A) Inner surface of the coil

If uncompressed length of spring is 40mm and number of coils 10mm, then pitch of coil is? a) 4 b) 40/9 c) 40/11 d) None of the mentioned

Description : If uncompressed length of spring is 40mm and number of coils 10mm, then pitch of coil is? a) 4 b) 40/9 c) 40/11 d) None of the mentioned

Last Answer : b) 40/9

DC relay coil or contactor coils must be connected to which side?

Description : DC relay coil or contactor coils must be connected to which side?

Last Answer : Negative side of the DC supply to avoid galvanic effect on the coil, which will corrode the coil.  

A close coil helical spring of mean diameter D consists of n coils of diameter d. If it carries an axial load W, the energy stored in the spring, is (A) 4WD²n/d 4N (B) 4W²Dn/d 4N (C) 4W²D3n/d 4N (D) 4W²D3n²/d 4N

Description : A close coil helical spring of mean diameter D consists of n coils of diameter d. If it carries an axial  load W, the energy stored in the spring, is  (A) 4WD²n/d 4N (B) 4W²Dn/d 4N (C) 4W²D3n/d 4N (D) 4W²D3n²/d 4N

Last Answer : (C) 4W²D3n/d 4N

A close coil helical spring when subjected to a moment M having its axis along the axis of the helix (A) It is subjected to pure bending (B) Its mean diameter will decrease (C) Its number of coils will increase (D) All the above

Description : A close coil helical spring when subjected to a moment M having its axis along the axis of the helix  (A) It is subjected to pure bending  (B) Its mean diameter will decrease  (C) Its number of coils will increase  (D) All the above 

Last Answer : (A) It is subjected to pure bending 

The windings of the electromagnetic are usually called: a. Magnetic coils b. Field coil c. Electric coil d. simple coil

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

A compression spring is made of music wire of 2 mm diameter having a shear strength and shear modulus of 800 Mpa and 80 Gpa respectively. The mean coil diameter is 20mm, free length is 40 mm, and the number of active coils is 10. If the mean coil diameter is reduced to 10 mm, the stiffness of the spring is approximately a. increased by 8 times b. decreased by 2 times c. increased by 2 times d. decreased by 8 times

Description : A compression spring is made of music wire of 2 mm diameter having a shear strength and shear modulus of 800 Mpa and 80 Gpa respectively. The mean coil diameter is 20mm, free length is 40 mm, and the number ... by 8 times b. decreased by 2 times c. increased by 2 times d. decreased by 8 times

Last Answer : a. increased by 8 times

What is the velocity factor of coaxial cable with a characteristic impedance of 50Ω and capacitance of 30pF/ft and inductance of 75 nH/ft? A. 0.58 B.0.68 C. 0.98 D. 0.81

Description : What is the velocity factor of coaxial cable with a characteristic impedance of 50Ω and capacitance of 30pF/ft and inductance of 75 nH/ft? A. 0.58 B.0.68 C. 0.98 D. 0.81

Last Answer : B.0.68

Define :i) Self inductance ii) Coefficient of self induction

Description : Define :i) Self inductance ii) Coefficient of self induction

Last Answer : i) Self-inductance: It is the property by virtue of which a coil opposes change in current flowing through it by inducing an emf in it such that its effect is to circulate current (induced current) that produces a magnetic field ...          N = di/dt        N = Φ/I  It is expressed in henry.  

What effect does flux leakage in a transformer have on the coefficient of coupling (K) in the transformer?

Description : What effect does flux leakage in a transformer have on the coefficient of coupling (K) in the transformer?

Last Answer : it causes K to be less than unity (I).

What effect does flux leakage in a transformer have on the coefficient of coupling (K) in the transformer?

Description : What effect does flux leakage in a transformer have on the coefficient of coupling (K) in the transformer?

Last Answer : it causes K to be less than unity (I).

What is meant by the coefficient of coupling?

Description : What is meant by the coefficient of coupling?

Last Answer : The ratio of the fines of force produced by one coil to the lines of force that link another coil. It is never greater than one.

What is coefficient of coupling? Explain in brief.

Description : What is coefficient of coupling? Explain in brief.

Last Answer : Coefficient of coupling (k):  It is defined as the ratio of actual mutual inductance present between two coils to the maximum possible value.  If L1 and L2 are coefficients of self ... K is less than one.  The coefficient of coupling is also called as Magnetic coupling Coefficient.

Calculate the characteristics impedance for a transmission line having L=0.5 mH/Km, C=0.08 µF and negligible R and G.

Description : Calculate the characteristics impedance for a transmission line having L=0.5 mH/Km, C=0.08 µF and negligible R and G.

Last Answer : L=0.5 mH/Km C=0.08 µF

When number of turns in a coil is trippled, without any change in the length of coil, its self inductance becomes? (1) Nine times (2) Three times (3) Six times (4) One-third

Description : When number of turns in a coil is trippled, without any change in the length of coil, its self inductance becomes? (1) Nine times (2) Three times (3) Six times (4) One-third

Last Answer : (1) Nine times

Three factors responsible for the change in voltage as load is applied to an AC generator are: 1) the drop in resistance in the armature circuit, 2) the change in flux, and 3) the ____________. A. armature winding speed B. inductance load drop C. coil pitch factor D. armature reactance voltage drop

Description : Three factors responsible for the change in voltage as load is applied to an AC generator are: 1) the drop in resistance in the armature circuit, 2) the change in flux, and 3) the ____________. A. armature winding speed B. inductance load drop C. coil pitch factor D. armature reactance voltage drop

Last Answer : Answer: D

An open coil in a transformer will be indicated by which of the listed conditions? A. 'zero' resistance accompanied by high inductance B. no resistance accompanied by stray inductance C. infinite resistance in addition to no inductance D. infinite resistance in addition to normal inductance

Description : An open coil in a transformer will be indicated by which of the listed conditions? A. 'zero' resistance accompanied by high inductance B. no resistance accompanied by stray inductance C. infinite resistance in addition to no inductance D. infinite resistance in addition to normal inductance

Last Answer : Answer: C

Brush sparking during commutation may be caused by ________. A. eddy currents in the armature core B. laminations in the generator field pieces C. induced current opposite to coil inductance D. coil inductance discharge occurring at commutation

Description : Brush sparking during commutation may be caused by ________. A. eddy currents in the armature core B. laminations in the generator field pieces C. induced current opposite to coil inductance D. coil inductance discharge occurring at commutation

Last Answer : Answer: D

The inductance of a coil is measured in _____________. A. ohms B. volts C. henries D. amperes

Description : The inductance of a coil is measured in _____________. A. ohms B. volts C. henries D. amperes

Last Answer : Answer: C

Alternating current circuits develop resistance, inductance and capacitance. The inductance of a coil is expressed in _____________. A. ohms B. mhos C. henrys D. farads

Description : Alternating current circuits develop resistance, inductance and capacitance. The inductance of a coil is expressed in _____________. A. ohms B. mhos C. henrys D. farads

Last Answer : Answer: C

Mention the inductance value of the peterson’s coil.

Description : Mention the inductance value of the peterson’s coil.

Last Answer : L=1/3wc2