Question

4. Which particles are responsible for flow of current in conductors?
5. Define potential at a point.
6. Define
(i) 1 volt
(ii) 1 Ampere
7. How much energy is given to each coulomb of charge passing through 6 V battery?
8. How is an ammeter connected in a circuit? Why?
9. How is a voltmeter connected in a circuit? Why?
10. Amount of charge flowing through a cell in 4 s is 12 C. Find the current supplied by the cell.
11. Calculate the number of electrons that would flow per second through the cross section of wire when 1A current flows through it?
12. If 2 x 10-3 J of work is done in moving a particle carrying a charge of 10 x 10-6 C from infinity to a point P. What will be the potential difference at that point?
13. An electric appliance draws a current of 0.4 A when the voltage is 220 V. Calculate the amount of charge flowing through it in one hour?
14. Find the number of electros transferred between two points kept at a potential difference of 20 V if 40 J of work is done.
15. Calculate the resistance of a resistor if the current flowing through it is 200mA, when the applied potential difference is 0.8 V?
16. State Ohm’s law. Draw the graph showing t he relation between potential difference and current.
17. What are the factors affecting resistance of a current carrying conductor?
18. What will happen to the current flowing through a conductor
(i) if the potential difference is doubled?
(ii) If the resistance is doubled?
19. A piece of wire of resistance of 6 Ω is connected to battery of 12 V. Find the amount of current flowing through it. Now the same wire is redrawn by stretching it to its double length. Find the resistance of the new (redrawn) wire.
20. A nichrome wire has a resistance of 10Ω.Find the resistance of another nichrome wire whose length is 3 times and area of cross section is 4 times the first wire.


can any1 answer this

Answer 1

Electric current is defined as the rate at which charge flows through a surface (the cross section of a wire, for example). Despite referring to many different things, the word current is often used by itself instead of the longer, more formal "electric current". The adjective "electrical" is implied by the context of the situation being described. The phrase "current through a toaster" surely refers to the flow of electrons through the heating element and not the flow of slices of bread through the slots.

As with all quantities defined as a rate, there are two ways to write the definition of electric current — average current for those who claim ignorance of calculus…

I̅ = ΔqΔt

and instantaneous current for those with no fear of calculus…

I = limΔq = dqΔt → 0Δtdt

The unit of current is the ampère [A], which is named for the French scientist André-Marie Ampère (1775–1836). In written languages without accented letters (namely English) it has become customary to write the unit as ampere and, in informal communication, to shorten the word to amp. I have no problem with either of these spellings. Just don't use a capital "A" at the beginning. Ampère refers to a physicist, while ampère (or ampere or amp) refers to a unit.

Since charge is measured in coulombs and time is measured in seconds, an ampère is the same as a coulomb per second.

⎡
⎣A = C⎤
⎦s

This is an algebraic relation, not a definition. The ampère is a fundamental unit in the International System. Other units are derived from it. Fundamental units are themselves defined by experiment. In the case of the ampère, the experiment is electromagneticin nature.

The ampère is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed one meter apart in vacuum, would produce between these conductors a force equal to 2 × 10−7 newton per meter of length.

This means that the coulomb is defined as the amount of charge that passes through a surface when a current of one ampère flows for one second.

[C = As]

When I visualize current, I see things moving. I see them moving in a direction. I see a vector. I see the wrong thing. Current is not a vector quantity, despite my well-developed sense of scientific intuition. Current is a scalar. And the reason is… because it is.

But wait, it gets weirder. The ratio of current to area for a given surface is known as the current density.

J = IA

The unit of current density is the ampère per square meter, which has no special name.

⎡
⎣A = A⎤
⎦m2m2

Despite being the ratio of two scalar quantities, current density is a vector. And the reason is, because it is.

Well… actually, it's because current density is defined as the product of charge density and velocity for any location in space…

J = ρv

The two equations are equivalent in magnitude as shown below.

J = ρ v  J = q ds = s dq = 1 IVdtsAdtA J = I A

Something else to consider.

I = JA = ρvA

Readers familiar with fluid mechanics might recognize the right side of this equation if it was written a bit differently.

I = ρAv

This product is the quantity that stays constant in the continuity equation.

ρ1A1v1 = ρ2A2v2

The exact same expression applies to electric current with the symbol ρ changing meaning between contexts. In fluid mechanics ρ stands for mass density, while in electric current it represents charge density.

microscopic description

Current is the flow of charged particles. They are discrete entities, which means they can be counted.

n = N/V

Δq = nqV

V = Ad = AvΔt

I = Δq = nqAvΔtΔtΔt

I = nqAv

Answer 2

Answer:

:There is a relationship between Current and charge. The relationship is as shown below:

Charge (Q) – charge is measured in coulombs (C).

Current (I) – is measured in amperes (A).

  Current is the rate of flow of charge. A current of 1 A means that 1 coulomb of charge flows past a point in a circuit every second. ( 1 A = 1 C s-1 ) Current is measured in a circuit using an ammeter which is placed in series with the component of interest in the circuit. Where current is equal to the change in charge over change in time

I=∆Q/∆t

From your question . How much charge?

This is Q=It

Therefore, 2x3=6 Coulombs

Explanation: plz mark me the brainliest

Explanation: