I want to make an electrical circuit like the picture i uploaded. This circuit will make the electromagnet on if LDR is illuminated and vice versa. I use 5v red laser to illuminate the LDR and i have 2 kind of LDR (in the picture, i use only one of them).
The question is:
1) what kind of transistor should i use and is it pnp or npn?
2) which LDR should i use?
3) if i replace potentiometer with resistor, what is the value of it?
you can modify my circuit but you cannot change the value of the battery, ldr, and electromagnet because i have only these. Also you can search the transistor from this site : http://alltransistors.com/.
The question is:
1) what kind of transistor should i use and is it pnp or npn?
2) which LDR should i use?
3) if i replace potentiometer with resistor, what is the value of it?
you can modify my circuit but you cannot change the value of the battery, ldr, and electromagnet because i have only these. Also you can search the transistor from this site : http://alltransistors.com/.