00:01
Hello everyone so let's start with the question so in a question there is a source of voltage of 106 volt which is connected to a series with a resistor value 1 .8 kilo and inductor having a value of 32 henry and the current is allowed to a reach its maximum okay so here it's having all the elevation of maximum current now at time t equal to zero a switch is thrown out and which disconnected the voltage source but learn to but we get to know the register and the inductor connected in this on circuit.
00:34
It means if the at time equal to zero, if the switch was turned out and the disconnection is was there, the voltage source.
00:43
So we came to know that the resistor and the inductor is connected there on in circuit.
00:48
So we have to find the how much time millisecond is needed for the current in the circuit to drop 9 percentage of its value at time equal to 0.
00:56
Okay, this is the 9 percentage of value it's at time and how much energy is in melee jule does the circuit dissipate during that time.
01:06
So let first i will show the diagram how it is connected.
01:09
So suppose this was a resistor and this is the inductor which is connected in a series to a point source of a voltage that is 106 and its value is 1 .8 kilo -oom and 32 handrail.
01:37
Now when the circuit reaches its maximum point, the switch is thrown out and the circuit become as shown as the part two.
01:45
So suppose this is a part one and it is a part two.
01:47
Suppose there was a disconnection in the source.
01:51
So it will look like this.
01:52
That is this is our voltage and here the resistor and index are playing along in their on circuit that is this will be 1 .8 kilo oom and current.
02:07
Is moving from here and this is 32 hand ray.
02:11
Now here when the current becomes maximum, suppose these are case two, when the current become maximum, let me write when current becomes maximum.
02:29
So i can write that is d i by dt equal to zero.
02:36
So as for the voltage law we can write that is vl equal to minus as.
02:42
D i divided by d t equal to zero so voltage across inductor is what zero okay so i can write here the vl is equal to zero and this is the formula okay for the inductor in terms of inductor value okay so i can write that is i not which is maximum at that point and it will be given by the formula of v divided by r so here voltage is given that is 106 divided by register value 1 point multiply by 10 to 3.
03:20
So we get our answer.
03:23
So after solving this we get our maximum current that is 58 .89 multiplied by 10 .2 minus 3 ampere...