Internal resistance of a battery is _ ohm, if E=l0V, Vt=9V, I= lA.

Explanation

The internal resistance (r) of a battery can be calculated using Ohm's law. Ohm's law relates the voltage (V) across a resistor to the current (I) flowing through it and the resistance (r) of the resistor:V = I * rGiven:E (emf or electromotive force of the battery) = 10 VVt (terminal voltage of the battery) = 9 VI (current flowing through the battery) = 1 AThe terminal voltage (Vt) of the battery is the voltage measured across its terminals when it is connected to an external circuit. It is related to the emf (E) and the internal voltage drop (V_drop) due to the internal resistance of the battery:Vt = E - V_dropWe can rearrange this equation to solve for the internal voltage drop:V_drop = E - VtSubstitute the given values:V_drop = 10 V - 9 VV_drop = 1 VNow, we can use Ohm's law to find the internal resistance (r):V_drop = I * r1 V = 1 A * rr = 1 V / 1 Ar = 1 ohmSo, the internal resistance of the battery is 1 ohm.