Last Answer : Req= (1/1200 +1/560 + 1/2.1)^-1 = 2.1 ohms RT= 2.1 + 7.8 = 9.9 ohms IT = V/R = 24/9.9 = 2.4 A Veq= R I = 2.1 2 ... 7.8 = 12.096 w = 44.928 w _________________________________________ By: Ellis-Junior Kamatjipose [email protected]
Description : 9 leds each of 1 volt drop is series with 9 volt battery , do we need a resistor?(SMD leds) I have seen some smd leds without resistor !
Last Answer : We connect resistor to limit the current. So, it depends upon the current rating of the LED, which is provided by manufacturer.
Description : A resistor of value R/2 is connected in parallel with a resistor of value R/3. The voltage drop across the parallel combination is V. The total current supplied by the voltage source is: w) 2 V/R (read: 2 V over R) x) 3 V/R (read: 3 V over R) y) 4 V/R (read: 4 V over R) z) 5 V/R (read: 5 V over R)
Last Answer : ANSWER: Z -- 5 V/R
Description : A 10 ohm and a 20 ohm resistor are connected in parallel to a current source. What fraction of the current flows through the 20 ohm resistor? w) 1/2 x) 1/3 y) 2/3 z) 3/4
Last Answer : ANSWER: X -- 1/3
Description : A 20 ohm resistor and a 60 ohm resistor are connected in parallel to a voltage source. If the current in the 60 ohm resistor is one ampere, the current in the 20 ohm resistor will be: w) 1/3 ampere x) 2/3 ampere y) 1 ampere z) 3 amperes
Last Answer : ANSWER: Z -- 3 AMPERES
Description : Current through each resistor when they are connected in series is A. different B. same C. can be both A and B D. decreasing
Last Answer : same
Description : A `5 Omega` resistor is connected in series with a parallel combination of n resistors of `6 Omega` each. The equivalent resistance is `7 Omega`. Find
Last Answer : A `5 Omega` resistor is connected in series with a parallel combination of n resistors of `6 Omega ... The equivalent resistance is `7 Omega`. Find n.
Description : `6Omega` and `12Omega` resistors are connected in parallel. This combination is connected in series with 10 V battery and `6 Omega` resistor. What is
Last Answer : `6Omega` and `12Omega` resistors are connected in parallel. This combination is connected in series with 10 V battery and ... 4 V B. 16 V C. 2 D. 8 V
Description : A five ohm and a ten ohm resistor are connected in parallel, what single resistance is "equivalent" to this combination?
Last Answer : ANSWER: 3 AND 1/3 OHM
Description : Two identical resistors are connected in parallel and consume 200 watts together. A third identical resistor is added in parallel. The total power consumed is: w) 100 watts x) 200 watts y) 300 watts z) 400 watts
Last Answer : ANSWER: Y -- 300 WATTS
Description : Which of the following statements regarding evacuated tube collectors (ETC) are true? i) ETC is used for high temperatures upto 150oC ii) because of use of vacuum between two concentric glass tube, higher amount of heat is ... upon the ambient temperature i & iii b) ii & iii c) i & iv d) i & ii
Last Answer : d) i & ii
Description : The purpose of resistor bank 'R1-R5' in the winch circuit shown in the illustration is to ______________. EL-0102 A. limit armature current in lower and 'series field' current in hoist to ... required speeds D. regulate the strength of the brake solenoid 'B1-B2' in both directions of operation
Last Answer : Answer: C
Description : A circuit has a resistance of 200 ohms. The resistance of the circuit can be reduced to 120 ohms by adding which of the following to the circuit. w) 80 ohm resistor in series x) 150 ohm resistor in parallel y) 240 ohm resistor in series z) 300 ohm resistor in parallel
Last Answer : ANSWER: Z -- 300 OHM RESISTOR IN PARALLEL
Description : An LED is operated on a 12 volt automobile circuit. The voltage drop across the LED is 2 volts and the current must be limited to 50 milliamps to prevent its overheating and destruction. What size resistor must be used? w) 60 ohms x) 100 ohms y) 120 ohms z) 200 ohms
Last Answer : ANSWER: Z -- 200 OHMS
Description : The ringing of an electric bell in an enclosed evacuated glass bell jar is not heard outside because - (1) the ringing is not loud enough (2) the glass of the bell jar absorbs the sound waves (3) the bell jar is too small (4) there is no air or any other gas in the bell jar
Last Answer : (4) there is no air or any other gas in the bell jar
Description : If current of 20 mA is passing through op-amp and voltage drop across series resistor is 10 V then value of resistance is A. 500Ω B. 400Ω C. 300Ω D. 200Ω
Last Answer : 500Ω
Description : A series circuit consists of a two ohm RESISTOR and a one ohm INDUCTOR. The relationship between current and voltage is: w) current will lag by 30 degrees. x) current will lag by 26 degrees. y) current will lead by 26 degrees. z) current will lead by 30 degrees.
Last Answer : ANSWER: X -- CURRENT WILL LAG BY 26 DEGREES.
Description : A 20 V battery of internal resistance `1 Omega` is connected to three coils of `12 Omega, 6 Omega` and `4 Omega` in parallel, a resistor of `5Omega` a
Last Answer : A 20 V battery of internal resistance `1 Omega` is connected to three coils of `12 ... and the terminal potential difference across each battery.
Description : Three identical cells each of emf 2 V and unknown internal resistance are connected in parallel. This combination is connected to a `5 Omega` resistor
Last Answer : Three identical cells each of emf 2 V and unknown internal resistance are connected in parallel. ... what is the internal resistance of each cell ?
Description : When a resistor is used as a shunt and is connected in parallel with a meter movement coil, it will provide _____________. A. a measurement of circuit resistance B. an increased accuracy of approximately 1.5 percent C. an extended meter range D. none of the above
Description : Four equal resistors are connected in parallel, each resistor has an ohmic value of 100 ohms, what is the equivalent resistance?
Last Answer : 25 ohms
Description : When 2,4 and 6 ohms resistor are connected in parallel their resultant equivalent resistance will be A. 12ohm b. 11/12ohm C. 12/11ohm d. None
Last Answer : C. 12/11ohm
Description : When an additional resistor is connected across an existing parallel circuit, the total resistance: A. remains the same B. decreases by the value of the added resistor C. increases by the value of the added resistor D. decreases
Last Answer : When an additional resistor is connected across an existing parallel circuit, the total resistance: decreases
Description : Three resistors of 4 Ω, 6 Ω and 9 Ω are connected in parallel. Which resistor consumes the maximum power? (A) 4 Ω (B) 6 Ω (C) 9 Ω (D) 17 Ω
Last Answer : (c) 9 ohm
Description : Three identical, each of emf 2 V and internal resistance `0.2 Omega` are connected in series to an external resistor of `7.4 Omega`. Calculate the cur
Last Answer : Three identical, each of emf 2 V and internal resistance `0.2 Omega` are connected in series to ... 7.4 Omega`. Calculate the current in the circuit.
Description : Two resistors of `6 Omega " and " 9 Omega` are connected in series to a 120 V source. The power consumed by the `6 Omega` resistor is
Last Answer : Two resistors of `6 Omega " and " 9 Omega` are connected in series to a 120 V source. The power consumed by ... 384 W B. 616 W C. 1500 W D. 1800 W
Description : Copper and carbon wires are connected in series and the combined resistor is kept at `0^(@)C`. Assuming the combined resistance does not vary with tem
Last Answer : Copper and carbon wires are connected in series and the combined resistor is kept at `0^(@)C`. Assuming the combined ... C)` A. 4 B. 8 C. 6 D. 2
Description : The equivalent resistance of two resistor connected in series is `6 Omega` and their equivalent resistance is `(4)/(3)Omega`. What are the values of r
Last Answer : The equivalent resistance of two resistor connected in series is `6 Omega` and their equivalent resistance is `(4 ... , 2 Omega` D. `6 Omega, 2 Omega`
Description : A 2 V battery, a `990Omega` resistor and a potentiometer of 2 m length, all are connected in series of the resistance of potentiometer wire is `10Omeg
Last Answer : A 2 V battery, a `990Omega` resistor and a potentiometer of 2 m length, all are connected in series of the resistance ... 0.01Vm^(-1)` D. `0.1Vm^(-1)`
Description : What is the phase angle of an ohm inductor in series with an ohm resistor connected to a 5 KHz source?
Last Answer : You need to provide values of resistor and inductor etc to find the phase angle.
Description : A series wound DC motor has its armature and field connected in series with a resistor. When the motor is disconnected from its power supply, this motor will exemplify __________. A. the ... the proper connections for an automatic strip heater C. a reversing controller circuit D. dynamic braking
Last Answer : Answer: D
Description : Motor controllers are seldom troubled with grounds because _____________. A. the auxiliary contacts have a high resistance connection B. the contactors and relays are mounted on a nonconducting panel ... individual series-connected units D. there are separate switches for the motor and the control
Last Answer : Answer: B
Description : Two series resistors are connected to an ac source. If there are 7.5 V rms across one resistor and 4.2 V rms across the other, the peak source voltage is? A.16.54 V B.1.65 V C.10.60 V D.5.93 V
Last Answer : Two series resistors are connected to an ac source. If there are 7.5 V rms across one resistor and 4.2 V rms across the other, the peak source voltage is? A.16.54 V B.1.65 V C.10.60 V D.5.93 V
Description : To limit the current flow through a DC voltmeter to as low a value as possible, the moving coil circuit is provided with a/an _____________. A. high series resistance B. high parallel resistance C. series inductor D. external shunt
Last Answer : Answer: A
Description : The fuse in an electric circuit is connected in – (1) series with neutral (2) parallel to live (3) parallel to neutral (4) series with live
Last Answer : (4) series with live Explanation: A fuse wire is a safety wire connected in series with the live wire that has high resistivity and low melting point. Fuses are always connected in ... large current supply or malfunctioning in the electric connections, it melts and breaks the electric circuit.
Description : If electric resistance is to be decreased, then the number of resistances should be connected in – (1) Series (2) Parallel (3) Mixed arrangement (4) None of these
Last Answer : (2) Parallel Explanation: Resistors are in parallel when each resistor is connected directly to the voltage source by connecting wires having riegligible resistance. Each resistor thus has the full voltage ... same full voltage of the source applied to it, but divide the total current amongst them
Description : The fuse in an electric circuit is connected in (1) series with neutral (2) parallel to live (3) parallel to neutral (4) series with live
Last Answer : series with live
Description : If electric resistance is to be decreased, then the number of resistances should be connected in _______ (1) Series (2) Parallel (3) Mixed arrangement (4) None of these
Last Answer : Parallel
Description : To electrically decrease the length of an antenna. A. add an inductor in series B. add an inductor in parallel C. add a resistor in series D. add a capacitor in series
Last Answer : D. add a capacitor in series
Description : Increasing the electrical length of an antenna means A. add an inductor in parallel B. add a capacitor in series C. add an inductor series D. add a resistor is series
Last Answer : C. add an inductor series
Description : The 'Choke' used with a tube light is basically – (1) an inductor (2) a capacitor (3) a transformer (4) a resistor
Last Answer : (1) an inductor Explanation: In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct ... created by suddenly interrupting the current in choke, which is connected in series with the tubelight.
Description : The ‘Choke’ used with a tube light is basically (1) an inductor (2) a capacitor (3) a transformer (4) a resistor
Last Answer : an inductor
Description : Current measuring instruments must always be connected in _____________. A. series with a circuit B. parallel with a circuit C. series-parallel with a circuit D. delta with the shunt
Description : Which of the following statements represents the main difference between a relay and a contactor? A. Contactors control current and relays control voltage. B. A relay is series connected and a contactor ... loads than relays. D. Contactors are made from silver and relays are made from copper.
Description : Average power dissipated in resistor if sinusoidal p.d of peak value 25 V is connected across a 20 Ω resistor is A. 15.6 W B. 15 W C. 16 W D. 17 W
Last Answer : 15.6 W
Description : A transformer has a turns ratio of two to one. If a 100 ohm resistor is connected on the high side, its resistance as measured on the low side would be: w) 25 ohms x) 50 ohms y) 100 ohms z) 400 ohms
Last Answer : ANSWER: W -- 25 OHMS
Description : Pure water is bad conductor of electricity because it is – (1) feebly ionized (2) not volatile (3) a very good solvent (4) a non-polar solvent
Last Answer : (1) feebly ionized Explanation: Pure water is a covalent compound. It exists as simple discrete molecules and have a simple molecular structure. Hence, it does not exist as ions. Therefore, ... into hydrogen ions and hydroxide ions. The presence of mobile ions enables it to conduct electricity.
Description : Pure water is bad conductor of electricity because it is (1) feebly ionized (2) not volatile (3) a very good solvent (4) a non-polar solvent
Last Answer : feebly ionized
Description : In the illustration, the signal from the device connected to terminals 18 and 19 is __________. EL-0046 A. prime mover speed feedback B. loss of control alarm when comparing with the input signal ... slip between the prime mover and the alternator D. to shut down the prime mover if overspeeding
Description : Four amperes of current are measured through a 24 ohms resistor connected across a voltage source. How much voltage does the source produce? A.960 V B.9.6 V C.96 V D.8 V
Last Answer : Four amperes of current are measured through a 24 ohms resistor connected across a voltage source. How much voltage does the source produce? A.960 V B.9.6 V C.96 V D.8 V