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Assume we have a purely inductive circuit such as below:

enter image description herevoltage source and inductor

To calculate the most general case, \$V_1\$ is given as such:

$$v(t) = V_m \cdot cos(\omega t+q)$$$$v(t) = V_m \cdot \cos(\omega t+\theta)$$

For an inductor, \$V = L \frac{di}{dt}\$\$v(t) = L \dfrac{\mathrm{d}i(t)}{\mathrm{d}t}\$. Writing it in integral form:

$$i(t=0)+\int_0^t v \,dt= i(t)$$$$i(0)+\int_0^t{v(t)\mathrm{d}t}= i(t)$$

Now consider \$i(t=0)=0\$\$i(0)=0\$, meaning there was no current in the system before the source was on:

$$\int_0^t V_m\cdot cos(\omega t+q) \,dt= i(t)$$$$\int_0^t{V_m\cdot \cos(\omega t+\theta) \mathrm{d}t}= i(t)$$

Moreover, the result of the integral, and hence the current:

$$\frac{V_m}{\omega}\cdot(sin(\omega t+q)-sin(q))= i(t)$$$$\dfrac{V_m}{\omega}\cdot(\sin(\omega t+\theta)-\sin(\theta))= i(t)$$

If transformed to their complex counterparts via \$e^{j\omega t} = cos(\omega t)+jsin(\omega t)\$\$\mathrm{e}^{j\omega t} = \cos(\omega t)+j\sin(\omega t)\$, the result, which is the impedance, is not \$j\omega L\$ but some term similar to \$j\omega L\$, but also containing the phase of the voltage source, which shouldn't be there, since impedance is not dependent on the phase of the source.

Where am I going wrong?

Assume we have a purely inductive circuit such as below:

enter image description here

To calculate the most general case, \$V_1\$ is given as such:

$$v(t) = V_m \cdot cos(\omega t+q)$$

For an inductor, \$V = L \frac{di}{dt}\$. Writing it in integral form:

$$i(t=0)+\int_0^t v \,dt= i(t)$$

Now consider \$i(t=0)=0\$, meaning there was no current in the system before the source was on:

$$\int_0^t V_m\cdot cos(\omega t+q) \,dt= i(t)$$

Moreover, the result of the integral, and hence the current:

$$\frac{V_m}{\omega}\cdot(sin(\omega t+q)-sin(q))= i(t)$$

If transformed to their complex counterparts via \$e^{j\omega t} = cos(\omega t)+jsin(\omega t)\$, the result, which is the impedance, is not \$j\omega L\$ but some term similar to \$j\omega L\$, but also containing the phase of the voltage source, which shouldn't be there, since impedance is not dependent on the phase of the source.

Where am I going wrong?

Assume we have a purely inductive circuit such as below:

voltage source and inductor

To calculate the most general case, \$V_1\$ is given as such:

$$v(t) = V_m \cdot \cos(\omega t+\theta)$$

For an inductor, \$v(t) = L \dfrac{\mathrm{d}i(t)}{\mathrm{d}t}\$. Writing it in integral form:

$$i(0)+\int_0^t{v(t)\mathrm{d}t}= i(t)$$

Now consider \$i(0)=0\$, meaning there was no current in the system before the source was on:

$$\int_0^t{V_m\cdot \cos(\omega t+\theta) \mathrm{d}t}= i(t)$$

Moreover, the result of the integral, and hence the current:

$$\dfrac{V_m}{\omega}\cdot(\sin(\omega t+\theta)-\sin(\theta))= i(t)$$

If transformed to their complex counterparts via \$\mathrm{e}^{j\omega t} = \cos(\omega t)+j\sin(\omega t)\$, the result, which is the impedance, is not \$j\omega L\$ but some term similar to \$j\omega L\$, but also containing the phase of the voltage source, which shouldn't be there, since impedance is not dependent on the phase of the source.

Where am I going wrong?

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calculating Calculating the impedance formula of an inductor

assumeAssume we have a purely inductive circuit such as below  :

enter image description here

toTo calculate the most general case, V1\$V_1\$ is given as such  : v(t)= Vm*cos(wt+q)

since , for$$v(t) = V_m \cdot cos(\omega t+q)$$

For an inductor: v=L di/dt, \$V = L \frac{di}{dt}\$. Writing it in integral form , :

$$i(t=0)+\int_0^t v \,dt= i(t)$$

nowNow consider, i(t=0)=0 \$i(t=0)=0\$, meaning there was no current in the system before the source iswas on.
$$\int_0^t Vm*cos(wt+q) \,dt= i(t)$$ moreover:

$$\int_0^t V_m\cdot cos(\omega t+q) \,dt= i(t)$$

Moreover, the result of the integral, and hence the current: $$(Vm/w)*(sin(wt+q)-sin(q))= i(t)$$

if$$\frac{V_m}{\omega}\cdot(sin(\omega t+q)-sin(q))= i(t)$$

If transformed to their complex counterparts via "e^jwt=cos(wt)+jsin(wt)" \$e^{j\omega t} = cos(\omega t)+jsin(\omega t)\$, the result  , which is the impedance, is  not coming as $$ jwL$$ but\$j\omega L\$ but some term similar "jwL"to \$j\omega L\$, but also containing the phase of the voltage source, which shouldn't be there, since impedance is not dependent on the phase of the source. where

Where am I doing thegoing wrong?

calculating the impedance formula of inductor

assume we have purely inductive circuit such as below  enter image description here

to calculate the most general case, V1 is given as such  : v(t)= Vm*cos(wt+q)

since , for inductor: v=L di/dt. Writing it in integral form , $$i(t=0)+\int_0^t v \,dt= i(t)$$

now consider, i(t=0)=0, meaning there was no current in the system before the source is on.
$$\int_0^t Vm*cos(wt+q) \,dt= i(t)$$ moreover, the result of the integral, and hence the current: $$(Vm/w)*(sin(wt+q)-sin(q))= i(t)$$

if transformed to their complex counterparts via "e^jwt=cos(wt)+jsin(wt)" , the result  , which is the impedance, is  not coming as $$ jwL$$ but some term similar "jwL" but also containing the phase of the voltage source, which shouldn't be since impedance is not dependent on the phase of the source. where am I doing the wrong

Calculating the impedance formula of an inductor

Assume we have a purely inductive circuit such as below:

enter image description here

To calculate the most general case, \$V_1\$ is given as such:

$$v(t) = V_m \cdot cos(\omega t+q)$$

For an inductor, \$V = L \frac{di}{dt}\$. Writing it in integral form:

$$i(t=0)+\int_0^t v \,dt= i(t)$$

Now consider \$i(t=0)=0\$, meaning there was no current in the system before the source was on:

$$\int_0^t V_m\cdot cos(\omega t+q) \,dt= i(t)$$

Moreover, the result of the integral, and hence the current:

$$\frac{V_m}{\omega}\cdot(sin(\omega t+q)-sin(q))= i(t)$$

If transformed to their complex counterparts via \$e^{j\omega t} = cos(\omega t)+jsin(\omega t)\$, the result, which is the impedance, is not \$j\omega L\$ but some term similar to \$j\omega L\$, but also containing the phase of the voltage source, which shouldn't be there, since impedance is not dependent on the phase of the source.

Where am I going wrong?

deleted 1 character in body
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assume we have purely inductive circuit such as below enter image description here

to calculate the most general case, V1 is given as such : v(t)= Vm*cos(wt+Qvwt+q)

since , for inductor: v=L di/dt. Writing it in integral form , $$i(t=0)+\int_0^t v \,dt= i(t)$$

now consider, i(t=0)=0, meaning there was no current in the system before the source is on.
$$\int_0^t Vm*cos(wt+q) \,dt= i(t)$$ moreover, the result of the integral, and hence the current: $$(Vm/w)*(sin(wt+q)-sin(q))= i(t)$$

if transformed to their complex counterparts via "e^jwt=cos(wt)+jsin(wt)" , the result , which is the impedance, is not coming as $$ jwL$$ but some term similar "jwL" but also containing the phase of the voltage source, which shouldn't be since impedance is not dependent on the phase of the source. where am I doing the wrong

assume we have purely inductive circuit such as below enter image description here

to calculate the most general case, V1 is given as such : v(t)= Vm*cos(wt+Qv)

since , for inductor: v=L di/dt. Writing it in integral form , $$i(t=0)+\int_0^t v \,dt= i(t)$$

now consider, i(t=0)=0, meaning there was no current in the system before the source is on.
$$\int_0^t Vm*cos(wt+q) \,dt= i(t)$$ moreover, the result of the integral, and hence the current: $$(Vm/w)*(sin(wt+q)-sin(q))= i(t)$$

if transformed to their complex counterparts via "e^jwt=cos(wt)+jsin(wt)" , the result , which is the impedance, is not coming as $$ jwL$$ but some term similar "jwL" but also containing the phase of the voltage source, which shouldn't be since impedance is not dependent on the phase of the source. where am I doing the wrong

assume we have purely inductive circuit such as below enter image description here

to calculate the most general case, V1 is given as such : v(t)= Vm*cos(wt+q)

since , for inductor: v=L di/dt. Writing it in integral form , $$i(t=0)+\int_0^t v \,dt= i(t)$$

now consider, i(t=0)=0, meaning there was no current in the system before the source is on.
$$\int_0^t Vm*cos(wt+q) \,dt= i(t)$$ moreover, the result of the integral, and hence the current: $$(Vm/w)*(sin(wt+q)-sin(q))= i(t)$$

if transformed to their complex counterparts via "e^jwt=cos(wt)+jsin(wt)" , the result , which is the impedance, is not coming as $$ jwL$$ but some term similar "jwL" but also containing the phase of the voltage source, which shouldn't be since impedance is not dependent on the phase of the source. where am I doing the wrong

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