00:01
In this problem, we have been given that there is a battery and the emf of this battery is 15 volt.
00:09
And this battery has some internal resistance so that the terminal voltage, which is the potential difference across the ends, and that is given as 11 .2 volts.
00:24
And let's take the internal resistance as r.
00:27
And this battery is connected to an external load resistor of resistance are oms.
00:35
And it is observed here that this battery delivers 26 watts of power to the external load resistor.
00:44
So the power that's dissipated by this resistor that is given as 26 watts and we are required to determine the value of this external load resistor and the internal resistance of this battery.
01:02
So first we can get the current which is flowing through this circuit and let's take that as i.
01:10
So according to the expression, v equals i times r, this is in accordance with om's law, let's use this.
01:17
So the potential difference across the load resistor, that is the terminal volume, of the battery so 11 .2 is equal to i times r and as this is the potential difference across this resistance so we can use the expression for electrical power and determine the current which is flowing through this resistor so as p is equal to v i we can replace i with we by r from this expression so we get p as v square that's 11 .2 square by r so from from here we can solve and get the value for the load resistor and that will be 11 .2 square over 26.
02:01
So when we square 11 .2 and divide this with 26, we're going to get the value of the load resistance coming out to be 4 .8 2 oms approximately...