Current electricity

What is emf?

It is the electric potential difference between 2 points when there is no charge present

What is the formula for potential (drop) in a circuit or resistor?

V = I*R

V → ELectric potential

I → Current

R → Resistance

What is the formula that gives the total emf of a battery that is charging?

E = V + Ir

Where,

E → total emf supplied

V → Terminal voltage

Ir = V_i = internal loss

What is the formula that gives the total emf of a battery that is dis-charging?

E = V - Ir

Where,

E → total emf supplied

V → Terminal voltage

Ir = internal  loss (due to internal resistance)

What is the formula for finding out the current distributed between circuits which have different resistances

What is the condition for a balanced wheat stone bridge?

What is the formula we will use to find the potential at the node

What are the formula for current?

I = Q/T

I = emf/Resistance

I = Delta V /R

Delta V = V _initial - V _final

Wat is teh formula that we will use to get emf equivalent and equivalent resistance when the emf’s are connected in parallel?

If the polarity changes somewhere, then you will add the negative sign there only specifically

What is the formula for finding our power inside a circuit?

P = i²r (or) i*e

P → Power

i → Current

r → Resistance

e → Emf of the cell

What is a null point??

In a meter bridge experiment, the null point is the exact position along the resistance wire where the galvanometer shows zero deflection.

What is the formula used for finding out the Shunt resistance??

What is current? What is its formula?

It is the amount of charge passing through an area per unit time (Which is usually 1 second). It’s formula is I =q/t

What is the speed of an electron?

10⁵ m/s

What is relaxation time?

It is the amount of time between 2 successive collisions between electrons

What is the relaxation time for a copper conductor?

10^-14 sec

What is the formula for finding out the specific resistivity in a circuit?

m → Mass

n → number of electrons

e → Electrons charge

t → Relaxation time

What is current density? What is its formula?

It is teh current passing per unit area perpendicular to it

Wha tis the formula for finding out the current inside a container having constant volume?

What is the formula that gives the relation between average kinetic energy and k_b and T?

What is the formula that gives the relationship between cunductivity and resistivity respectively?

What is the formula for mobility?

v_d → Drift velocity

E → Electric field

t → Relaxation time

What are practical units?

They are units that are easier to use in real-life measurements, especially in labs or engineering work.

What is teh SI unit for obility ad what is the value for its practical units?

SI unit → cm²/Vs; 10⁴