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State the principal and working of a meter bridge?
On what factors the internal resistence of a cell depends ?
Calculate the de-Broglie's wavelength associated with an electron of energy 200eV .What will be the change in its wavelength if the accelerating potential is increased to four times its earlier value?
Draw an equipotential surface due to an electric dipole.
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.
derivation for ampere circuital law?
How to solve an unbalanced Wheatstone bridge?
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)
how can sensitivity of potentiometer be increased
What is the dimensional formula of potential difference
An equiconvex lens of refractive index mu1, focal length f and radius of curvature R is immersed in a liquid of refractive indec mu2. Find the focal length of the lend in terms of original focal length and the refractive index of glass of lens and that of medium.
What is the definition of meter bridge?
hc = 1242eV nm. how ?
h ki value toh 6.636 smthng h fer yhan kya li h apne ?
What are the conditions for total internal reflection?
the emf of a cell is always greater than its terminal voltage.why?give reason.
why is potentiometer preferred over voltmeter?
How is I=Qv and I=QA please explain. these formulae have been used in my guide.
what is the dimension of resistance....????
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??
a copper wire is streched to make it 0.1%lonnger.what is the percentage change in resistance?
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
what is vacus junction?
A 80uF capacitor is charged by a 50V battery.The capacitor is disconnected from the battery and then connected across another uncharged 320 uF capacitor. Calcuulate the charge on the second capacitor.
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 ?
Three cells of emf 2V,1.8V and 1.5V are connected in series.Their internal resistances are 0.05ohm, 0.7ohm and 1ohm respectively.If the battery is connected to an external resistor of 4ohm via a very low resistance of ammeter, what would be the reading in the ammeter?
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?
A steady current flows in a metallic conductor of non-uniform cross section.Which of these quantities is constant along the conductor-
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.
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....
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?
Compute the voltage drop across a 2 KW electric heater element whose resistance when hot is 20 ohm.
Explain the variation of conductivity nwith temp for (a) A metallic conductor (b) ionic conductor
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.
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
why is it safe to sit inside a car during a thunderstorm ?
Draw V-I Graph for both ohmic and non-ohmic materials stating one example of each as well.
Pls describe Callender-Griffith's Bridge and Carey-Phoster's Bridge
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?
derive the expression for drift velocity in an electric field.
Why current density is a vector quantity when electric current is a scalar quantity?
what are kirchhoff's law?explain them.
give two possible causes for one sided deflection in a potentiometer experiment.
A piece of copper of mass 50 g is drawn into a wire of length 50 m. Find the resistence of the wire . The density and specific resistence of copper are 8.9 * 10^3 kg m^-3 and 1.7 * 10^-8 ohm-m
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
1 NEWTON =how many dyne?
A cylindrical metallic wire is stretched to increase its length by 5%. Calculate the percentage change in its resistance.
two identical cells whether joined in series or in parallel gives the same current when connected to an external resistance of 1ohm. find the internal resistance of each cell.
what is the main difference between DC n AC current???
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