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appended answer 371480 as supplemental
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Nick Alexeev
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I have been trying a lot to get my circuit work. I want the led to light up when the LDR receives no light and vice versa. I have found that the LDR offers the resistance of approximately 6k ohms when light is expoosedexposed on it and 66k ohms when light is not exposed to it. So I have used the resistors with those value. But I am not being able to achieve it enter image description herein the simulator. Also there is glowing of the led in which lesser current is flowing but there is no glowing when more current is flowing. Please point out my mistakes and suggest me to get my circuit work. I want the current to flow through the transistor "only" when there is light exposed to the LDR  (possibly by keeping the low resistance for this path compared to the closed path of the LED). And when there is darkness, the current should not flow through the transistor leaving only a single path for the current to pass i.e. through the LED. Thanks for the help.

edit: The source in the collector circuit needs a ground return. Why is it so?

I have been trying a lot to get my circuit work. I want the led to light up when the LDR receives no light and vice versa. I have found that the LDR offers the resistance of approximately 6k ohms when light is expoosed on it and 66k ohms when light is not exposed to it. So I have used the resistors with those value. But I am not being able to achieve it enter image description herein the simulator. Also there is glowing of the led in which lesser current is flowing but there is no glowing when more current is flowing. Please point out my mistakes and suggest me to get my circuit work. I want the current to flow through the transistor "only" when there is light exposed to the LDR(possibly by keeping the low resistance for this path compared to the closed path of the LED). And when there is darkness, the current should not flow through the transistor leaving only a single path for the current to pass i.e. through the LED. Thanks for the help.

I have been trying a lot to get my circuit work. I want the led to light up when the LDR receives no light and vice versa. I have found that the LDR offers the resistance of approximately 6k ohms when light is exposed on it and 66k ohms when light is not exposed to it. So I have used the resistors with those value. But I am not being able to achieve it enter image description herein the simulator. Also there is glowing of the led in which lesser current is flowing but there is no glowing when more current is flowing. Please point out my mistakes and suggest me to get my circuit work. I want the current to flow through the transistor "only" when there is light exposed to the LDR  (possibly by keeping the low resistance for this path compared to the closed path of the LED). And when there is darkness, the current should not flow through the transistor leaving only a single path for the current to pass i.e. through the LED. Thanks for the help.

edit: The source in the collector circuit needs a ground return. Why is it so?

added the explanation further
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G-aura-V
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I have been trying a lot to get my circuit work. I want the led to light up when the LDR receives no light and vice versa. I have found that the LDR offers the resistance of approximately 6k ohms when light is expoosed on it and 66k ohms when light is not exposed to it. So I have used the resistors with those value. But I am not being able to achieve it enter image description herein the simulator. Also there is glowing of the led in which lesser current is flowing but there is no glowing when more current is flowing. Please point out my mistakes and suggest me to get my circuit work. I want the current to flow through the transistor "only" when there is light exposed to the LDR(possibly by keeping the low resistance for this path compared to the closed path of the LED). And when there is darkness, the current should not flow through the transistor leaving only a single path for the current to pass i.e. through the LED. Thanks for the help.

I have been trying a lot to get my circuit work. I want the led to light up when the LDR receives no light and vice versa. I have found that the LDR offers the resistance of approximately 6k ohms when light is expoosed on it and 66k ohms when light is not exposed to it. So I have used the resistors with those value. But I am not being able to achieve it enter image description herein the simulator. Also there is glowing of the led in which lesser current is flowing but there is no glowing when more current is flowing. Please point out my mistakes and suggest me to get my circuit work. Thanks for the help.

I have been trying a lot to get my circuit work. I want the led to light up when the LDR receives no light and vice versa. I have found that the LDR offers the resistance of approximately 6k ohms when light is expoosed on it and 66k ohms when light is not exposed to it. So I have used the resistors with those value. But I am not being able to achieve it enter image description herein the simulator. Also there is glowing of the led in which lesser current is flowing but there is no glowing when more current is flowing. Please point out my mistakes and suggest me to get my circuit work. I want the current to flow through the transistor "only" when there is light exposed to the LDR(possibly by keeping the low resistance for this path compared to the closed path of the LED). And when there is darkness, the current should not flow through the transistor leaving only a single path for the current to pass i.e. through the LED. Thanks for the help.

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G-aura-V
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Use of transistor for switching the led

I have been trying a lot to get my circuit work. I want the led to light up when the LDR receives no light and vice versa. I have found that the LDR offers the resistance of approximately 6k ohms when light is expoosed on it and 66k ohms when light is not exposed to it. So I have used the resistors with those value. But I am not being able to achieve it enter image description herein the simulator. Also there is glowing of the led in which lesser current is flowing but there is no glowing when more current is flowing. Please point out my mistakes and suggest me to get my circuit work. Thanks for the help.