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20 Physics -- DC Circuits

State Ohm's law .

State Ohm's law .

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Ohm's law states that the current flowing through a conductor is directly proportional to the voltage applied across it, given that the temperature and other physical conditions remain constant. Mathematically, Ohm's law is expressed as:

V = I * R

where V represents the voltage across the conductor, I represents the current flowing through the conductor, and R represents the resistance of the conductor.

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A storage battery of emf 8V and internal resistance 0.5ohm is discharged through a parallel combination of to resistor each of resistance 15 ohm. What is the terminal voltage of the battery?​ [3]a)...

Emf =8V,

Internal resistance r=0.5Ω
R1 = R2 = 15 Ω

Equivalent capacitance of R1 and R2 is

R= 7.5 Ω

now,

emf = I (R+r)
8 = I (7.5+0.5)

8 = I 8
I = 1A

Now,

E= IR+ Ir
E = V + Ir
8 = V + 1x0.5

V= 7.5 volt


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