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What are the combinations of NOR & NAND gate

no , I am asking their combinations like
2 NAND gate makes
3 NAND gate makes which gate
same as NOR
2NOR , 3 NOR

what their combinations are called
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They themselves are the combinations
NOR GATEOR GATE + NOT GATE
NAND GATE AND GATE + NOT GATE
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What is POYNTING VECTOR ? &
What does it represent ?

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In physics, the Poynting vector represents the directional energy flux density (the rate of energy transfer per unit area) of an electromagnetic field. The SI unit of the Poynting vector is the watt per square metre (W/m^{2}).
The Poynting vector is defined as
<dl> <dd></dd> </dl>where
 E is the electric field vector;
 H is the magnetic field's auxiliary field vector.
 S is Poynting vector
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When a wire of resistance R is streched and its radius becomes r/2 , then new resistance is ?

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Ans. Let the Initial Length of Wire = l
Final length of Wire = L
Intial Radius of wire = r
FInal Radius of Wire r_{1} = {tex}r\over 2{/tex}
So, Initial Volume of Wire = Final Volume of Wire
{tex}=> \pi r^2 l = \pi r_1^2L{/tex}
{tex}=> r^2 l = ({r\over 2})^2L{/tex}
{tex}=> r^2 l = {r^2\over 4}L{/tex}
{tex}=> L = 4l{/tex}
Initial Area of Cross Section of wire (A) = {tex}\pi r^2{/tex}
Final area of Cross section of wire (A') = {tex}\pi r_1^2 = \pi{r^2\over 4}{/tex}
Initial Resistance of Wire (R)= {tex}\rho {l\over A} = \rho {l\over \pi r^2}{/tex}
Final Resistance of Wire (R') = {tex}\rho {L\over A'} = \rho {4l\over {\pi r^2\over 4}} ={ \rho 4\times 4l\over\pi r^2}{/tex}
= {tex}16\rho{l\over \pi r^2} = 16R{/tex}
So new Resistance ll be 16 times of initial Resistance.
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Can there be a lower limit to the force acting between 2 equally charged particles saperated by the distance of 1 cm

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In finding electric field due to thin plane sheet that area of cylinder is A then why we take it as area for lateral surfaces for which fluxes exists

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Calculate the charge on alpha particle. Given charge on a proton = +1.6 × 10^{19} C.

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An alpha particle is basically a Helium atom without electrons, and it consist two proton.
Charge On 1 Proton = {tex}1.6\times 10^{19}C{/tex}
Charge on Alpha particle {tex}He^{+2} = 2\times 1.6\times 10^{19}C = 3.2\times 10^{19}C{/tex}
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How many electrons must be removed from a piece of metal to give it a positive charge of 1 × 10^{7 }C ?

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Let the number of electrons removed be n
Charge on one electron = {tex} 1.6 \times 10^{19} {/tex}
Then
{tex}=> n \times 1.6 \times 10^{19} = 1\times 10^{7}{/tex}
{tex}=> n = {1\times 10^{7} \over 1.6 \times 10^{19} }{/tex}
{tex}=> n = 6.25 \times 10^{11} {/tex}
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Calculate the total positive or negative charge on 3.11 g copper penny. Given Avogadro number = 6.02 × 10^{23} and atomic number of copper = 29 and atomic mass of copper = 63.5

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Calculate the Charge on _{26}F^{56 }nucleus.
Given the charge on proton = 1.6 × 10^{19}C.
(with process please solve it)

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What is electric force?

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The attractive or repulsive interaction between any two charged objects is an ELECTRIC FORCE
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What is an investigatory project?

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An investigatory project is basically any science experiment where you start with an issue or problem and conduct research or an investigation to decide what you think the outcome will be.
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Proof for relation between coulomb and stat coulomb

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Two point charges +3AC and +8Ac repel each other with force of 40N If charge of 5uC is added to each of them, a then the force between them will becomes

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<a> </a>a particle is moving with constant speed v along x axis in positive direction. Find the angular velocity of the particle about the point (0,b) when the position of the particle is (a,0)

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why electric fields inside the conductor is zero
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Because charge inside it is zero
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Sir if we know that any 2 like charges repel then why we need to prove that electric field doesn't cross over each other by drawing a tangent at a PT?
Will the board give us marks if we explain the way above?

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what is what is the electric flux offside once

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Define 1C of charge

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Ans. 1C of Charge is equal to the quantity of charge transferred in one second by a steady current of one ampere. It is equivalent to 6.2415 × 10^{18} elementary charges, where one elementary charge is the positive charge of a proton or the negative of the charge of an electron.
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What is electric dipole in case of equatorial line field?

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Electric field due to an electric dipole at a point on the equatorial line is given as
{tex}E = {1\over 4\pi \in_0} {p\over r^3}{/tex}
The direction of electric dipole moment is from q(negative charge) to +q(positive charge) and the resultant electric field at any point on equatorial line is in direction opposite to the electric dipole moment.
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Two similar charges Q are seperate by a certain distance a third q is placed between them are in such way that all the there charges are in equilibrium .find the magnitude from the other similar charge?

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If a body contain odd electrons and another uncharged body is placed in contact with then no of electrons on first body will become?

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According to the symmetry and conservation of charge both the bodies will have equal amount of charge I.e. half...
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why the direction of dipole is taken to be from ve to +ve?

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Ans. The torque on a dipole is given by,
{tex}\overrightarrow \tau = \overrightarrow p + \overrightarrow E{/tex}
The torque obtained is positive when the direction of the dipole is taken from negative charge to positive charge.
Another reason is, in analogy with magnetic dipole where field outside the magnet is from North to South while field within the magnet is from South to North, the direction of electric dipole within the dipole is taken from negative charge to positive charge (this is just an analogy that is followed, in practical direction of electric lines of force is always from positive to negative charge).
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Distinguish between electrostatic and electric charge?

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Ans.
 Electrostatics is a branch of physics that deals with the phenomena and properties of stationary or slowmoving electric charges. Electric chare is study.
 Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic fiel. Electric chare is what we study in Electrostatic.
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Is the exam paper of improvement is held with the compartment paper or it is separate ???

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If i appear in the improvement exam of 2 subjects physics n math then my final marks given to me as a new marksheet or not

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Distance of the centre of mass of a uniform cone from its vertex is z. If the radius of the cone is R and its height is h then find the value of z.

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Find the condition under which the charged particals moving with different speeds in the presence of electric and magnetic field vectors can be used to select charged particals of a particular speed.

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A Person is running at a maximum speed of 4m/s to catch a train.When he is 6 metre away from the door of compartment,the train starts to leave at a constant acceleration of 1m/s .Find the time taken by person to catch train.

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Ans. Let Train cover a distance d before man caught it in t time.
So, Distance covered by man S = 6+d m
Initial Speed of man u = 4m/s
As man is running with constant speed, So a = 0
Using
{tex}S = ut +{1\over 2}at^2{/tex}
{tex}=> 6+d = 4t +{1\over 2}\times 0\times t^2{/tex}
{tex}=> 6+d = 4t +0{/tex}
{tex}=> d = 4t 6 {/tex}………(1)
Similarly initial Speed of Train u = 0
acceleration a = 1m/s^{2}
Distance traveled = d
So,
{tex}=> d = 0\times t+{1\over 2}\times 1\times t^2{/tex}
{tex}=> d ={ 1\over 2} t^2{/tex}………(2)
From (1) & (2)
{tex}=> 4t6 = {1\over 2}t^2{/tex}
{tex}=> 8t12 = t^2{/tex}
{tex}=>t^2 8t+12 =0{/tex}
On solving we get,
t = 6s or 2s
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What is capacitance of a conductor? What is energy change if a conductor slab is inserted between the plate of capacitor?

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If a question is in parts,if answered in shuffled way marks will be deduced?

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