21 views
in Electrical Engineering by

Your answer

Thanks for your contribution. Feel free to answer this question. Please avoid short answer. Your answer is most welcome. Be genuine.

Upload image or document:

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
Are you a robot ? (Y = Yes / N = No)
To avoid this verification in future, please log in or register.

1 Answer

0 votes
by

Resistance of a wire is r ohms. The wire is stretched to double its length, then its resistance in ohms is  4 r.

Related questions

2 answers 31 views

What happens to the resistance of a wire when its length as well as the cross-sectional area are doubled? A) It doubles B) It becomes 4 times C) It becomes 2π times D) It remains the same

asked Apr 29, 2018 in Electrical Engineering by Shimroz123
1 answer 37 views

If a wire conductor of 0.2 ohm resistance is doubled in length, its resistance becomes?

asked Mar 25, 2018 in Basic concepts by Shimroz123
1 answer 16 views

If Poisson's ratio of a resistance wire strain gauge is 1.8, then neglecting piezo-resistive effects, its Gauge factor is :  (A) 2.8 (B) 2.6 (C) 4.6 (D) 3.6

asked Apr 30, 2018 in Electrical Engineering by Shimroz123
1 answer 25 views

If resistance is 20 Q. and inductance is 27 in a R-L series circuit, then time constant of this circuit will be?

asked Mar 25, 2018 in Electrical Engineering by Shimroz123
0 answers 20 views

When ‘n’ resistances each of value ‘r’ are connected in parallel, then the resultant resistance is ‘x’. When these ‘n’ resistances are connected in series, total resistance is  (A) n2X (B) X/n (C) n2/X (D) nX2

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
0 answers 17 views

A binary ladder with R -2R network has R = 20K Ohms. The total resistance looking out toward the LSB input is (a) 20KOhms (b) 40KOhms (c) 10KOhms (d) 30KOhms

asked Apr 14, 2018 in Electrical Engineering by Shimroz123
1 answer 82 views

A drawn wire of resistance 5 Ω is further drawn so that its diameter becomes one-fifth of the original. What is its resistance with volume remaining the same ? (a) 25 Ω (b) 125 Ω (c) 625 Ω (d) 3125 Ω

asked Apr 25, 2018 in Electrical Engineering by Shimroz123
0 answers 92 views

 When The dc converter in figure shown has a resistance load of R = 10 Ω and the input voltage is Vs 220 V the converter switch remains on, its voltage drop is Vo -2 V. The chopping frequency is fI K sW Vs If the duty cycle is 50%, determine: (a) the average output voltage V (b) the RMS output voltage Vo (c) the converter efficiency (d) the effective input resistance of the converter

asked Apr 26 by Hussein
1 answer 22 views

If the diameter of a conductor of 10 ohms is doubled, its new resistance would be? A.20 ohms B.5 ohms C.40 ohms D.2.5 ohms

asked May 15, 2018 in Basic concepts by Shimroz123
1 answer 61 views

If the insulation resistance of a cable of length 10 km is 1 mega ohm, its insulation resistance for 50 km length will be

asked May 8, 2018 in Electric Power Transmission by Shimroz123
1 answer 13 views

When a dipole antenna of 1/8 length has an equivalent total resistance of 1.5 Watt then the efficiency of the antenna is   (A) 0.89159% (B) 8.9159% (C) 89.159% (D) 891.59%

asked May 17, 2018 in Electronics communication by Shimroz123
1 answer 9 views

 If the field circuit resistance of a d.c. generator exceed its critical value, then the generator : -  a) fails to build up b) builds up a very high voltage c) exceeds its current capacity d) produces power beyond its rating 

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 21 views

The r.m.s. value of a sinusoidal A.C. current is equal to its value at an angle of______degrees.

asked Mar 24, 2018 in Electrical Engineering by Shimroz123
0 answers 13 views

A 6V zener diode is used to provide voltage regulation with a series resistance of 100 Ohms and supply voltage is 12V. When under no load the power dissipated in the zener diode is (a) 60mW (b) 36mW (c) 360mW (d) 3600mW

asked Apr 14, 2018 in Electrical Engineering by Shimroz123
0 answers 23 views

If both the number of turns and core length of an inductive coil are doubled, then its self inductance will be (a) halved (b) doubled (c) quadrupled (d) unaffected

asked May 25, 2018 in Inductance by Shimroz123
0 answers 49 views

A high-pass filter has a resistance R = 2 kΩ The lowest input frequency to be passed is 7.5 kHz. The value of suitable coupling capacitor must be: A) 0.001 pico Farad B) 0.01 pico Farad C) 0.1 pico Farad D) 1 pico Farad

asked Jun 4, 2018 in Electrical Engineering by Shimroz123
1 answer 328 views

A trolley wire weighs 1.2 kg per meter length. The ends of the wire are attached to two poles 20 meters apart. If the horizontal tension is 1500 kg find the dip in the middle of the span?

asked Mar 22, 2018 in Engineering Mechanics by Shimroz123
0 answers 114 views

If X is the system reactance and R is its resistance, the power transferred is maximum when (1) X=R (2) X=1.414 R (3) X=1.732 R (4) X=2R 

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 50 views

An A.C. voltage is impressed across a pure resistance of 3.5 ohms in parallel with a pure inductance of impedance of 3.5 ohms?

asked Mar 25, 2018 in Electrical Engineering by Shimroz123
0 answers 21 views

A dc shunt motor runs at 500 r.p.m at 220 V. A resistance of 4.5 Ω is added in series with the armature for speed control. The armature resistance is 0.5 ohms. The current to stall the motor will be (1) 44 A (2) 50 A (3) 44.4 A (4) 60 A  

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
0 answers 121 views

Two heater wires of equal length are connected first in series and then in parallel. The ratio of heat generated from series to parallel connection will be (a) 4 : 1 (b) 2 : 1 (c) 1 : 2 (d) 1 : 4

asked May 25, 2018 in Electrical Engineering by Shimroz123
1 answer 191 views

A 10 km long line has a characteristic impedance of 400 ohms. If line length is 100 km, the characteristic impedance is: (1) 4000 Ω (2) 400 Ω (3) 40 Ω (4) 4 Ω

asked May 28, 2018 in Electric Power Transmission by Shimroz123
1 answer 25 views

If the energy is supplied from a source, whose resistance is 1 ohm, to a load of 100 ohms the source will be?

asked Mar 25, 2018 in Network Analysis by Shimroz123
0 answers 19 views

DC ammeter has a resistance of 0.1 Ω and its current range is 0-100 A. If the range is to be extended to 0-300 A, what shunt resistance need to be connected?  A) 0.025 Ω B) 0.05 Ω C) 0.015 Ω D) 0.03 Ω

asked Apr 9, 2018 in Electrical Engineering by Shimroz123
1 answer 13 views

An ammeter has a current change of 0—5A and its internal resistance is 0.2 ohm. In order to Change the range to 0-25 A, wear need to add a resistance of  A) 0.8 ohm in series with the meter B) 1.0 ohm in series with the meter C) 0.04 ohm in parallel with the meter D) 0.05 ohm in parallel with the meter

asked May 20, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 41 views

In an induction motor if the flux density is reduced to one-half, of its normal value then the torque will  (1) reduce to one-half (2) reduce to one-fourth (3) remain unchanged (4) increase four times

asked May 1, 2018 in Electrical Machine by Shimroz123
1 answer 17 views

A 35 V dc supply is connected across a resistance of 600 ohm in series with an unknown resistance R. A voltmeter having a resistance of 1.2 kOhm is connected across 600 ohm resistances and reads 5 V. The value of resistance R shall be:

asked May 22, 2018 in Electrical Engineering by Shimroz123
0 answers 18 views

A parallel combination of capacitance C and resistance R is connected in series with inductance L and small resistance r. Under what condition will the circuit be non-reactive?  (A) C=LR (B) C=LR2 (C) C=L/R2 (D) C=L/R

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
0 answers 17 views

The current coil of a wattmeter is connected to the C.T. of R phase. Its potential coil is connected across Y & B phases. The wattmeter measures (a) active power in R phase (b) active power of Y-phase (c) reactive power in R-phase (d) power proportional to 3-phase power if the load is balanced 

asked May 25, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 23 views

A 10A DC Ammeter has a resistance of 0.1 Ω is to be extended to 50 A, the required shunt wire is A) Manganin wire of 20 m Ω B) Constantan wire of 20 m Ω C) Manganin wire of 25 m Ω D) Constantan wire of 25 m Ω

asked Jun 4, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 18 views

 A copper wire of length l and diameter d has potential difference V applied at its two ends. The drift velocity is vd . If the diameter of wire is made d/3, then drift velocity becomes

asked Mar 31, 2018 in Electrical Engineering by Shimroz123
1 answer 31 views

The r.m.s. value of a half-wave rectified alternating current is 10 A. Its value for full-wave rectification will be  

asked May 25, 2018 in Electrical Engineering by Shimroz123
1 answer 16 views

When an antenna of input resistance 73 ohm is connected to a 50-ohm line and if the losses are ignored then its efficiency will be nearly   (A) 0.19 (B) 0.81 (C) 0.97 (D) 1.19

asked May 17, 2018 in Electronics communication by Shimroz123
1 answer 62 views

What is the resistance of a 160 m wire with a uniform diameter of 0.28 mm, if the specific resistance is 12.32 μΩ-cm? A) 3.2 Ω B) 3.2 μΩ C) 0.8 Ω D) None of these

asked Apr 29, 2018 in Electrical Engineering by Shimroz123
0 answers 91 views

A conductor is composed of seven identical copper strands, each having a radius 'R'. Then what is self GMD (Geometric Mean Distance) of the conductor?  (A) 2.645 R (B) 2.177 R (C) 2.141 R (D) 1.21 R 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
0 answers 27 views

A high pass filter has a resistance R = 2 kΩ. The lowest input frequency to be passed is 7.5 KHz. The value of suitable coupling capacitor must be : (A) 0.1 pF (B) 1 pF (C) 0.1 μ F (D) 1 μ F

asked Mar 31, 2018 in Electrical Engineering by Shimroz123
1 answer 27 views

The resistance of a few meters of wire conductor in closed electrical circuit is?

asked Mar 25, 2018 in Basic concepts by Shimroz123
0 answers 28 views

A series R-L circuit is suddenly connected to d.c. voltage source of V volts. The current in this series circuit, just after the switch is closed, is equal to (1) Zero (2) V/L (3) V/C (4) V.L/C 

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 14 views

A resistor with the color coded value of 1000 ohms and ± 10% tolerance can have an actual resistance between ________. A. 990 ohm and 1010 ohm B. 900 ohm and 1100 ohm C. 1000 ohm and 1100 ohm D. 900 ohm and 1000 ohm. 

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
1 answer 18 views

Consider the star network shown in figure. The resistance between terminals A and B with C open is 6 ohms, between terminals B and C withAopen is 11 ohms and between terminals C andAwith B open is 9 ohms. Then RA, RB, RC respectively is 

asked May 20, 2018 in Network Analysis by Shimroz123
1 answer 23 views

When n resistances each of value r are connected in parallel, then resultant resistance is x. When these n resistances are connected in series, total resistance is

asked Mar 31, 2018 in Electrical Engineering by Shimroz123

Welcome to electronics2electrical.com here you can ask questions related to electrical, electronics, mechanical, telecommunication, instrumentation, computer, mathematics, physics etc.
Be respectful to all the members. Do not copy and paste the answers from other websites which have copyright content. While asking question give full details about it.

Categories

Most popular tags

power motor dc circuit transformer voltage current used system phase resistance factor synchronous load ac energy induction electric generator series frequency between speed capacitor use electrical meter line difference control type mosfet transmission magnetic plant high single instrument bjt unit source advantages function diode and machine winding field define torque parallel amplifier supply shunt thyristor motors electricity arduino maximum time relay armature problem value on transformers types coil diagram state flow ratio material three formula starting direction theorem method emf operating efficiency digital wave microprocessor test instruments inductance loss measure operation connected signal low applications effect single-phase network temperature working constant losses different law wattmeter measuring compare controlled breaker drive device logic rc full switch flux wire resistivity disadvantages free of materials machines angle force converter conductor transistor gain open protection scr core measurement number bridge principle generators reactance circuits negative the friction iron loop short pole battery conservation steam resistors hysteresis computer using analog lines secondary station gate a rectifier inverter linear induced relays nuclear capacitance basic characteristics design direct work rotor electronics ammeter forces diesel damping rlc connection factors capacitors minimum insulation moving regulation running self systems air fault range main stability quality starter igbt eddy alternator ideal rl average 3-phase plants arc thermal error fuzzy biasing dielectric pressure balanced superposition errors copper rotation feedback impedance measured electronic electrons charge inductive transfer explain start off back curve over solar is three-phase tariff locomotive peak bias zener engineering commutator surge conductors rating universal potentiometer density permanent mechanical transducer capacity memory adc excitation two fuse pure harmonics application semiconductor inductor internal pmmc reaction welding resonance traction permeability breakers rms designed electromagnetic si generation brushes switching capacitive shaded rate 1 distribution resistor methods delta star oscillator reluctance simplification algebra 8085 boolean weston dynamometer insulating strength installation definition fuel heating earth units

8,471 questions

7,069 answers

134 comments

3,088 users

...