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State the principal and working of a meter bridge?
On what factors the internal resistence of a cell depends ?
Draw an equipotential surface due to an electric dipole.
thet 3 identical resistors R1,R2 and R3 are connected to a battery as shown in the fig. what wil b d ratio of voltages across R1 andR2?
why are alloys manganin constantan used to make standard resistance coil?
A 3 m long copper wire carrying a current of 3 A.. How long does it take for an electron to drift from one end to other end ? The cross- sectional area of the wire is 2 * 10 ^ -6 m2 and the number of conduction electrons in copper is 8.5 * 10 ^ 28 m-3 .
project onto study various factors on which the internal resistance/emf of a cell depends.
Define 1 Ampere.
A cell of emf 4V and internal resistance .5 ohms is connected across a load of resistance: i)7.5 ohms ii)11.5 ohms.calculate i) the ratio of the differenceas in the emf of the cell and the potential drop across the load, ii)the ratio of the currents in the two cases.this qustion is wrt potentiometer.sir i wolud like to get a response as soon as possible.
derivation for ampere circuital law?
How to solve an unbalanced Wheatstone bridge?
how can sensitivity of potentiometer be increased
A 200-V bulb takes a current of 0.2 A. The length of its filament is 22 cm and the specific resistance of the material of the filament is 7 * 10^-5 ohm-cm. Find the radius of the filament. (pi=22/7)
What is the dimensional formula of potential difference
What is the definition of meter bridge?
What are the conditions for total internal reflection?
Drift Speed of Electrons is of the order of 10-3 ms-1, but current is established in the circuit with the speed of Light. Explain
the emf of a cell is always greater than its terminal voltage.why?give reason.
Abattery is connected across a variable external resistance R. When the current is 6A, the terminal potential difference is 8.4V ; when the current is 8A, the terminal potential difference is 7.2V. Find theEMF and the internal resistance.
why is potentiometer preferred over voltmeter?
what is the dimension of resistance....????
a copper wire is streched to make it 0.1%lonnger.what is the percentage change in resistance?
what is vacus junction?
A balloon starts rising from ground rest with an upward acceleration 2 m/secsqu. just after 1 sec. a stone is dropped from it the time taken by stone to strike the ground is nearly?
the resistance of the platinum wire of a platinum resistance thermometer at the ice point is 5 ohm and at steam point is 5.23 ohm .When the thermometer is inserted in a hot bath , the resistance of the platinum wire is 5.795 ohmcalculate the temprature of the bath
what are the advantages of potentiometer over votlmeter ?
show that electric field is conservative?
In a galvanometer there is deflection of 10 divisions per mA.Thje internal resistance of the galvanometer is 60 ohm.If a shunt of 2.5 ohm is connected to the galvanometer and there are 50 divisions in all,on the scale of galvanometer,what maximum current can this galvanometer read?
MY DOUBT IS:(If wrong plz correct it and explain) Since there are 50 divisions in all in the galvanometer,then maximum current that galvanometer would read is Ig=50*1/10=5 mA .But the answer is given 125 mA.How?
how does drift velocity of electron in a metallic conductor vary with temperature?
derive relation between current density and potential difference across a current carrying conductor of length l,area of cross section A and number density of free electron n
A steady current flows in a metallic conductor of non-uniform cross section.Which of these quantities is constant along the conductor-
1)Current
2)Current density
3)Drift speed
4)Electric field
Four resistances of 8, 8, 8 and 12 OHM form a Wheatstone network. What shunt is needed across the 12 OHM resistor to balance the network?
A resistance or R ohm draws a current from a potentiometer.The potentiometer has a total resistance R0 ohm.A voltage V is supplied to the potentiometer .Derive an expression for the voltage fed to the ckt when the slide is in the middle of the potentiometer.
A wire of resistance 8R is bent in the form of a circle. What is the effective resistance between the ends of a diameter AB?
Explain the variation of conductivity nwith temp for (a) A metallic conductor (b) ionic conductor
how does the balancing point of wheatstone bridge get affectde1. position of cell and galvanometre are interchanged
2. position of known and unknown resistance is interchanged
Two conducting wires X and Y of same diameter but different material are joined in series across the battery. If the number density of electron in X is twice that in Y, fined ratio of drift velocity of electron in two wires
a uniform wire of resistance 36 ohm is bent in tne form of a circle .calculate the effective resistance across the points A and B.
In example no 3.6 at page 116 of NCERT Physics, the value of R is found to b 5/6 ohm.. bt i think that it's incorrect.. it shud b 5/4 ohm...
Even if v put the valur of R=5/6 ohm in the formula I=V/R then v dnt get the current I as 4 A.. But on putting R=5/4 ohm, v get the correct value of I too. So it shud b 5/4 and not 5/6....
Isnt it.....????????
is current is scalar or vector quantity?
The supply voltage to a room is 120V.The resistance of lead wires is 6 ohm.A 60 W bulb is already switched on.What is the decrease of voltage across the bulb when a 240 W heater is switched on in parallel with the bulb?
a)0 V b)2.9 V c)13.3 V d) 10.04 V
My Question:
Draw V-I Graph for both ohmic and non-ohmic materials stating one example of each as well.
thanks!
a wire of 15 ohm resistance is gradually stretched to double its original length. it is then cut into two equal parts. these parts are connected in parallel across a 3 V cell. find the current drawn from the cell
A storage battery of emf 8V and internal resistance 0.5 ohm is being charged by a 120 V d.c supply using a series resistor of 15.5 ohm. What is the terminal voltage of the battery during charging? what is the purpose of having a series resistor in the charging ciruit?
12 identical resistance R each form a cube . Resistance across its face diagonal corners is?
How is I=Qv and I=QA please explain. these formulae have been used in my guide.
derive the expression for drift velocity in an electric field.
what are kirchhoff's law?explain them.
give two possible causes for one sided deflection in a potentiometer experiment.
why is a copper wire used in a sonometer to find the frequency of A.C mains?plz i hv my board practicals 2morow.friends and xperts plz help
the resistance of a silver wire at 0 degree celsius is 1.25 ohm.upto wat temp. it must b heated so dat its resistance is doubled?(alpha silver=0.00375/degree celsius.will d temp. be same for all silver conductors of all shapes??
1 NEWTON =how many dyne?
two cells of emf's 4.5v and 6v and resistance 6 & 3 Ohm have their -ve terminals joined by a wire of 18 Ohm and +ve terminal joines by a wire f 12 ohm . A third resisitance of wire 24 ohms of these wires . Draw circuit diagram and using kirchoffs rule find potential difference at the end of the third wire
A cylindrical metallic wire is stretched to increase its length by 5%. Calculate the percentage change in its resistance.
what is the main difference between DC n AC current???
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Syllabus
State the principal and working of a meter bridge?
On what factors the internal resistence of a cell depends ?
Six cells, each of emf 5V and internal resistance 0.1 ohm are connected as shown in Figure. The reading of the ideal voltmeter V is:
Draw an equipotential surface due to an electric dipole.
thet 3 identical resistors R1,R2 and R3 are connected to a battery as shown in the fig. what wil b d ratio of voltages across R1 andR2?
why are alloys manganin constantan used to make standard resistance coil?
A 3 m long copper wire carrying a current of 3 A.. How long does it take for an electron to drift from one end to other end ? The cross- sectional area of the wire is 2 * 10 ^ -6 m2 and the number of conduction electrons in copper is 8.5 * 10 ^ 28 m-3 .
project onto study various factors on which the internal resistance/emf of a cell depends.
Define 1 Ampere.
A cell of emf 4V and internal resistance .5 ohms is connected across a load of resistance: i)7.5 ohms ii)11.5 ohms.
calculate i) the ratio of the differenceas in the emf of the cell and the potential drop across the load, ii)the ratio of the currents in the two cases.
this qustion is wrt potentiometer.
sir i wolud like to get a response as soon as possible.
derivation for ampere circuital law?
How to solve an unbalanced Wheatstone bridge?
how can sensitivity of potentiometer be increased
A 200-V bulb takes a current of 0.2 A. The length of its filament is 22 cm and the specific resistance of the material of the filament is 7 * 10^-5 ohm-cm. Find the radius of the filament. (pi=22/7)
What is the dimensional formula of potential difference
What is the definition of meter bridge?
Thank you
What are the conditions for total internal reflection?
Drift Speed of Electrons is of the order of 10-3 ms-1, but current is established in the circuit with the speed of Light. Explain
the emf of a cell is always greater than its terminal voltage.why?give reason.
Abattery is connected across a variable external resistance R. When the current is 6A, the terminal potential difference is 8.4V ; when the current is 8A, the terminal potential difference is 7.2V. Find theEMF and the internal resistance.
why is potentiometer preferred over voltmeter?
what is the dimension of resistance....????
a copper wire is streched to make it 0.1%lonnger.what is the percentage change in resistance?
what is vacus junction?
A balloon starts rising from ground rest with an upward acceleration 2 m/secsqu. just after 1 sec. a stone is dropped from it the time taken by stone to strike the ground is nearly?
Q. For the circuit shown calculate the potential difference between point B and D.
the resistance of the platinum wire of a platinum resistance thermometer at the ice point is 5 ohm and at steam point is 5.23 ohm .When the thermometer is inserted in a hot bath , the resistance of the platinum wire is 5.795 ohmcalculate the temprature of the bath
what are the advantages of potentiometer over votlmeter ?
show that electric field is conservative?
10^9 electrons pass from A to B in 10^-3 second.Calculate the strength of current and give its direction.
ans is 1.6*10^-7A.
1. 1A, 0A, 1A
2. 2A, 1A, 1A
3. 1A, 0.5A, 0.5A
4. None of these
1)60 W bulb will fuse. 2)100 W bulb will fuse 3)both bulbs will fuse.
4)Bulbs will not fuse
Ans 200 ohm,5*10^-3 A.
Dont give link.
In a galvanometer there is deflection of 10 divisions per mA.Thje internal resistance of the galvanometer is 60 ohm.If a shunt of 2.5 ohm is connected to the galvanometer and there are 50 divisions in all,on the scale of galvanometer,what maximum current can this galvanometer read?
MY DOUBT IS:(If wrong plz correct it and explain) Since there are 50 divisions in all in the galvanometer,then maximum current that galvanometer would read is Ig=50*1/10=5 mA .But the answer is given 125 mA.How?
10. In the following circuit diagram the value of resistance X for the potential difference between B and D is zero -
a) 4 ohm
b) 6 ohm
c) 8 ohm
d) 9 ohm
how does drift velocity of electron in a metallic conductor vary with temperature?
derive relation between current density and potential difference across a current carrying conductor of length l,area of cross section A and number density of free electron n
1) 2:3
2) 2:1
3) 1:2
4) 1:1
A steady current flows in a metallic conductor of non-uniform cross section.Which of these quantities is constant along the conductor-
1)Current
2)Current density
3)Drift speed
4)Electric field
Four resistances of 8, 8, 8 and 12 OHM form a Wheatstone network. What shunt is needed across the 12 OHM resistor to balance the network?
A resistance or R ohm draws a current from a potentiometer.The potentiometer has a total resistance R0 ohm.A voltage V is supplied to the potentiometer .Derive an expression for the voltage fed to the ckt when the slide is in the middle of the potentiometer.
82. The equivalent resistance of the circuit between points O and A is
A wire of resistance 8R is bent in the form of a circle. What is the effective resistance between the ends of a diameter AB?
Explain the variation of conductivity nwith temp for (a) A metallic conductor (b) ionic conductor
how does the balancing point of wheatstone bridge get affectde1. position of cell and galvanometre are interchanged
2. position of known and unknown resistance is interchanged
Two conducting wires X and Y of same diameter but different material are joined in series across the battery. If the number density of electron in X is twice that in Y, fined ratio of drift velocity of electron in two wires
No links plzz...
The network PQRS shown in the circuit diagram has the battery of 4V and 5V and negligible internal resistance. A milliammeter of resistance is connected between P and R. Calculate the reading in the ammeter.
a uniform wire of resistance 36 ohm is bent in tne form of a circle .calculate the effective resistance across the points A and B.
In example no 3.6 at page 116 of NCERT Physics, the value of R is found to b 5/6 ohm.. bt i think that it's incorrect.. it shud b 5/4 ohm...
Even if v put the valur of R=5/6 ohm in the formula I=V/R then v dnt get the current I as 4 A.. But on putting R=5/4 ohm, v get the correct value of I too. So it shud b 5/4 and not 5/6....
Isnt it.....????????
is current is scalar or vector quantity?
(1).Diode
(2).Thyristor
(3).PN junction system
(4).All of these
The supply voltage to a room is 120V.The resistance of lead wires is 6 ohm.A 60 W bulb is already switched on.What is the decrease of voltage across the bulb when a 240 W heater is switched on in parallel with the bulb?
a)0 V b)2.9 V c)13.3 V d) 10.04 V
My Question:
Draw V-I Graph for both ohmic and non-ohmic materials stating one example of each as well.
thanks!
a wire of 15 ohm resistance is gradually stretched to double its original length. it is then cut into two equal parts. these parts are connected in parallel across a 3 V cell. find the current drawn from the cell
ans is 6*10^-4, 3.75*10^15
A storage battery of emf 8V and internal resistance 0.5 ohm is being charged by a 120 V d.c supply using a series resistor of 15.5 ohm. What is the terminal voltage of the battery during charging? what is the purpose of having a series resistor in the charging ciruit?
12 identical resistance R each form a cube . Resistance across its face diagonal corners is?
34. Two cells of emf 4 V and 3 V having internal resistance of 3 ohm and 1 ohm respectively are connected in parallel so as to send a current through an external resistance of 5 ohm in the same direction. Find the current through the cells and the current through the external resistance.
35. A coil having an inductance of 200 mH and resistance 10 ohm is connected to a 220 V, 50 Hz ac supply. Calculate the (a) impedance of the circuit and (b) the current in the circuit.
36. Find the angle of minimum deviation produced by an equilateral prism of refractive index 1.55. Also find the angle of incidence of minimum deviation.
37. Obtain the amount (mass) of ; (= 5.3years) necessary to provide a radioactive source of 5.0mCI
strength.
Draw the circuit diagram and using Kirchhorf's laws, calculate the current through each branch of the circuit and potential difference across the 5 ohm resistor.
How is I=Qv and I=QA please explain. these formulae have been used in my guide.
derive the expression for drift velocity in an electric field.
what are kirchhoff's law?explain them.
give two possible causes for one sided deflection in a potentiometer experiment.
why is a copper wire used in a sonometer to find the frequency of A.C mains?plz i hv my board practicals 2morow.friends and xperts plz help
the resistance of a silver wire at 0 degree celsius is 1.25 ohm.upto wat temp. it must b heated so dat its resistance is doubled?(alpha silver=0.00375/degree celsius.will d temp. be same for all silver conductors of all shapes??
1 NEWTON =how many dyne?
Please answer
Solutions on paper pls.
two cells of emf's 4.5v and 6v and resistance 6 & 3 Ohm have their -ve terminals joined by a wire of 18 Ohm and +ve terminal joines by a wire f 12 ohm . A third resisitance of wire 24 ohms of these wires . Draw circuit diagram and using kirchoffs rule find potential difference at the end of the third wire
A cylindrical metallic wire is stretched to increase its length by 5%. Calculate the percentage change in its resistance.
Q. Find the current through the 10 ohm resistance connected across AB.
what is the main difference between DC n AC current???