Current Electricity Questions and Answers

6 In the given network find the 12 V a 4Q www 12 8 V 492 292 a potential difference between a and b b currents in each branch

3 9 Determine the current in each branch of the network shown in Fig 3 30 10 02 50 50 50 1002 HH 1002 FIGURE 3 30 10V

In the circuit shown current in different branches are marked Select the correct alternative s 3VT XX 1 1 A in 120 i 1 1 1 692 2922 ww 14 292 13 192 T1V 6 1 2 la A 18

Find the equivalent resistance between points A and B if each resistor is of resistance r A 1 4r 3 3 ww B www w www 2 ww 2r 3 4 r

Object having charge of 4 C is given 9 10 electrons Calculate the net charge on the object Two spherical balls of the same radius carry charges 0 4 C and 0 9 C Calculate the number of electrons to be transferred from one ball to another such that they attain the same charge

5 An object with a net po Calculate the number of electrons present on it A spherical ball is given one million electrons per second Calculate the time required by the ball to attain a charge of 0 8 C An object with an initial charge of 4 C is given 9 x 10 9 additional electrons horge on the object

The potential difference between the points A and B in the following circuit shown in the figure 50 1 volt 8 volt 502 552 Awwww 2V 12 5 0 www 501 W 552 www B 4 2 volt 5 4 2 volt

A resistance R 12 2 is connected across a source of emf as shown in the figure Its em changes with time as shown in the graph If the heat developed in the resistance in the first fou seconds is K Joule Find the value of K 10 E V 24 4 t s R 12Q www E source

20 A potential difference of 2 5 V is applied across the faces of a germanium crystal plate The face area of the crystal is 1 cm2 and its thickness is 1 0 mm The free electron concentration in germanium is 2 x 1019 m 3 and the electron and holes mobilities are 0 33 m2 V s and 0 17 m2 V s respectively The current across the plate will be 1 0 2 A 2 0 4 A 3 0 6 A 4 0 8 A

In given network potential drop across A and B is 1 Zero 49 8 V Bo wwwwwww 42 42 8V 2 8 V

Find the minimum number of cells required to produce a current of 1 5 A through a resistance of 30 2 Given that the emf of each cell is 1 5 V and the internal resistance is 19

ample 40 a lution b a A W Find the equivalent resistance between A and B of the network extending off to the infinity shown in the figure R R CR A E R Im R A WWW R R E R D R R If E 12 V R 12 and R 42 find the current in R nearest to the battery Let the equivalent resistance of the given infinite ladder is R Since the network extend infinity the resistance of the network to the right of the points C and D is also equal t Hence R R R and so on M RR A 2R RE

30 Reading of an ideal voltmeter in the circuit belo 1 V 1 V 1 V 1 Zero 3 4 V HHH 1Q 19 wwwwwwww V 19 www 6 V 2 2 V 4 6 V

cells are connected as shown A IV 2V 20 C and resistance 702 Part AC is 20cm long Two resistors and two idea 1 50 B Of the points A B and C the potential is maximum at point A A B B

5 A circuit containing five resistors is connected to a battery with a 12 V emf as shown in figure The potential difference across 49 resistor is 1 3 V 2 6 V 3 9 V www 292 52 wwww wwww 20 9 www 69 12 V 492 www

22 In the following circuit the magnitude of potential 2 difference between A and B is R 2 A 151 15 V A 1 10 V 2 5 V 3 15 V 4 7 5 V B 52 0

If in a p n junction diode a square input signal of 10 V is applied as shown Then the output signal across R will be AIEEE 2007 11 5 V 2 10 V 5 V A IT R 5 V 3 T IT T 5 VI

A capacitor of capacitance 50 F charged to 1000 V is connected to resistor of resistance 40 k as shown A voltmeter of resistance 40 kQ is connected across the resistor The switch S is closed at t 0 the reading of voltmeter at t 1 s is 40 kQ 1 Zero 2 632 V V www 40 kQ 50 F H 1000V S

Two conducting wires of same length are made from the same material One wire is solid with diameter 1 mm while the other is hollow with outer diameter 2 mm and inner diameter 1 mm The ratio of their resistances will be A 1 2 C 3 1 B 1 3 D 2 1

Find the i effective emf across AB ii current assuming R 102 6 V r 1 5 4 V and 12 2 A www 81 II E r1 W B 6 V 2

11 Consider the following circuit 10V A 252 252 10V f 5V C 192 252 2 52 5V B 10V A Current between C and D is 2 5 A B Current between A and D is IA C There is atleast one resistor in the circuit which does not carry current

114 The potential difference across 802 resistance is 48 V as shown in the figure The value of potential difference across X and Y point will be a 168 V c 152 V 240 2012 b 100 V d 48 V

m 4 A hollow spherical ball of inner radius a and outer radius 2a is made of a uniform material of constant thermal conductivity K The temperature within the ball is maintained at 2T and outside the ball it is To Find a the rate at which heat flows out of the ball in the steady state b the temperature at r 3a 2 where r is radial distance from the centre of shell Assume steady state condition a 2a 2T K

141 Current through wire XY of circuit shown is a 1 A 2 A 12 www 3Q X Y 50 V 252 wwwww 4Q b 4 A d 3 A

art of a circuit in steady state along with the currents flowing branches the value of resistances etc is shown in the figure answer the following questions Current in the 202 resistor is A I A C 3 A Potential difference between points P and Q is A 10 V C 30 V Charge on the capacitor is A 10 C C 20 C HH 3V B 20 V D 35 V 2A B 80 C D 40 C 2A 10 10 30 P 4uF www 30 a 1A 22 1A 50 www www Sd 10 www 402

will result in no credit Partial 4 In the circuit shown in Figure 4 find a the current in resistor R b the resistance of the resistor R and c the unknown emf E Figure 4 28 0 V E R www 4 00 A www 6 00 6 00 A

7 Find the equivalent resistance for the circuit in the figure below left R R R

the network of seven resistors shown in the figure below Find the value of the single equivalent resistor that could be used to replace the entire resistor network Assume the following values for the circuit elements 5 00 V R 37 02 R 4 00 S Re 6 00 2 Rd 5 00 2 R 7 00 Rj 14 0 R 16 0 2 Contents Ra W Rg www Rf www Rb Rd W Rc Back Re I Top Image size S M L Max Scroll to

Valerie s 169 4 W flat iron is plugged into a 120 V line in her bedroom What current does the flat iron draw

A 21 volt battery provides 3 5 amperes of current to a light bulb How many ohms of resistance does the light bulb have Round your answer to the nearest 0 1 Do not add units

Analyze the given electical circuit by finding the unknown currents NOTE Enter your answers exactly 4 V A 4 V 36 3 V 3Q M I 492 w 12 59 ww 13 B

Calculate the time it takes for 40 3 C to drift through a wire carrying 17 5 A

How much voltage is required to push 2 5 A of current across a 18 ohm resistor Round your answer to the nearest 0 1 Do not add units

7 Find the charge on the capacitor in an LRC series circuit at t 2 seconds when L 1 25h R 3N C 0 2 E t 0V q 0 6C and q 0 i 0 0A Round your answer to four decimal places

A voltage of 100 V is placed across a resistance of 15 8 Q What is the current that will be forced through the resistor Round your answer to the nearest 0 1 tenths place Do not add units

Physical Science Electricly Magnetiam Electrical Power and Energy What is the equation for POWER used by an electrical appliance What is the equation for electrical ENERGY used by an appliance Name Part A Use the power equation to solve for current voltage or power used by each appliance 1 05 amperes of current go through a cordless curting iron powered by a 9 voll battery How much power is used by the curling iron 2 A 110 velt wall outlet supplies power to a strobe light The current flowing through the light is 0 05 amperes How much power is used by the strobe light 3 ACD player has a current of 0 1 amps flowing through it If the CD player uses 0 4 watts of power what is the voltage of the CD player s battery 4 A television is plugged into a 120 volt wall outlet It uses 360 watts of power What current flows through the television Part B Use the electrical energy equation to calculate the power length of time or electrical energy used by each appliance 5 A hair dryer is used for 7 5 hours one month It uses 600 watts of power on average How much electrical energy does the hair dryer use in a month How much would it cost to use the hair dryer each month if the rate charged by the electric company is 0 09 per kWh Physical Science Name 6 A stereo is used for 90 hours per month It costs 0 88 to run the stereo each month If the electric company charges 0 09 per kWh what electric energy is used by the stereo What power is used 7 A color television uses 15 0 kWh of electric energy each month If the television uses 200 watts of power each month how many hours does it run 8 A laptop is used for 3 hours a day If the voltage of the laptop battery is 19 5 volts and the current is 4 62 amps what electric energy does the laptop use each day Part C Find the power or energy used by each appliance You may have to use ohm s law to find the current or voltage first 9 A remote control is powered by two 1 5 volt batteries If the resistance is 6 ohms find the current flowing through the remote control and then find the power used by the remote control 10 If the remote control in the above problem is used for a total of 3 5 hours how much electrical energy does it use 11 A camera has a resistance of 3 ohms A current of 1 ampere flows through the camera when it is in use Solve for the voltage of the battery in the camera and then find the power used by the camera 12 Find the electrical energy used by the camera in the above problem if the camera Runs for 150 minutes

Substances through which charges move easily are called Select one O a insulators Ob conductors Oc electators

ANSWER QUESTION 1 or 2 then ANSWER 3 4 5 and 6 1 Find the Current through each Branch of the network below show steps and work to get your final BRANCH currents 270 R E 4 in HSV 1 R Mon E 110 V 2 R 320

As more lamps are put into a parallel circuit the overall current in the power source Select one a stays the same b increases C decreases

If a 298 4 W heater has a current of 4 6 A what is the resistance of the heating element Don t include the unit

For a constant resistance a quadrupling of the voltage drop across an electrical device will cause the current through it to be Select one O a unchanged O b one fourth as much O c four times as much

Three resistors with values of 16 0 18 0 and 14 Q are connected in parallel What is their equivalent resistance Don t include unit

If the potential difference across a pair of batteries used to power a flashlight is 6 7 V what is the potential difference across the flashlight bulb

A 12 V battery is attached to a 12 Q resistor and an unknown resistor R2 as shown below There is a total current of 3 A CYMB 12v 3a R 1202 R2 the total rocistance of the circuit b What is the value of R c Find the current across each resistor

10 Transformers are used both to increase the voltage of electricity so that it can travel long distances and to decrease the voltage so that the electricity can be used in your house with relative safety If the voltage across two wires is raised to 2 5 10 V what is its current if 1 0 10 W of power is provided 11 Calculate the amount of power dissipated by this electric heating element if the generator s output voltage is 110 volts and the heater s resistance is 2 5 ohms Now calculate the power dissipated by the same heater if the generator s output voltage is doubled 12 A bulb is plugged into a 120 Volt outlet The Resistance of the bulbs is 330 0 a Calculate the current b Calculate the power c Calculate the work done in 15 seconds 13 A current of 4 5A runs through a lamp with a resistance of 60 ohms in 1 minute What is the work done on the lamp

A 60 watt light bulb is a light bulb that Select one O a O b O c Od produces 60 J of light energy every second produces 60 J of energy for every 1 amp of current that passes through it produces 60 J of energy for every 1 Coulomb of charge that passes through it contains 60 J of energy

Three resistors are wired in series with a 22 0 V battery The resistances are 22 5 Q 33 6 0 and 9 9 Q What is the voltage across each resistor

How much charge passes a point in a wire carrying a current of 7 5 A for a period of 26 1 sec

The current through a 69 0 resistor connected to a 91 V power supply is

Shown are copper wires of identical cross sectional area Which wire will have the least resistance A B C D Im Im E of 20 C 0 06 5m 5m at 20 C at 80 C