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current drawn by led increase with more leds you put which i saw in a video about thyristor ,but more leds means more resistance which means lesser current which is not true as per the video(https://youtu.be/4N1uLth1o9o )1:50-2:00that does not fall true how and why. PS -the channel is GreatScott's so its reliable

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    \$\begingroup\$ LEDs are not resistors. \$\endgroup\$ – DKNguyen Aug 21 '19 at 18:50
  • \$\begingroup\$ if you run 4 hoses into a bucket, you can fill it 4x faster. if you run those same 4 hoses end to end to the bucket, it will take longer to fill than one hose. \$\endgroup\$ – dandavis Aug 21 '19 at 20:52
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The LEDs he is using have an internal resistor or constant-current chip (there are no external series resistors as is normal).

When you connect them in parallel across a fixed voltage, each will draw a certain amount of current (depending on the LED and the voltage). Put 5 similar ones in parallel and you get about 5x the current that you get with one.

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  • \$\begingroup\$ the LEDs are plain jane LEDs, no resistors or CC \$\endgroup\$ – dandavis Aug 21 '19 at 20:50
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More LEDs (or resistors) in parallel means more paths for current to flow = less effective resistance.

Connecting resistors in series will increase the total resistance - total resistance will be the sum of the individual resistor values.

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Current drawn by led increase with more leds you put which i saw in a video about thyristor.

The LEDs in the video were connected in parallel.

They are now acting like 4 times the original load (Single LED). The intention in the video is to simply I increase the load is about Thyristor latching.

The LEDs are also turned on without a current limiting element. It is not a good idea. The supply voltage there is just 2.7 V right about the forward voltage drop plus the additional drop in thyristor. enter image description here

But more LEDs means more resistance

Hypothetically, yes if you connect them in series (considering the leads resistance in m ohms). Same way when you connect in parallel, it will be lesser than single LED one. But the change will be of no use to consider.

Connecting more LEDs in the video is like turning on more bulbs in the house. The current will have to increase.

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  • \$\begingroup\$ "The supply voltage there is just 2.7 V right about the forward voltage drop." - Red LEDs typically drop about 1.8 V, not 2.7 V; the difference is dropped in the thyristor. \$\endgroup\$ – marcelm Aug 21 '19 at 19:23
  • \$\begingroup\$ @marcelm I bit my foot \$\endgroup\$ – Umar Aug 21 '19 at 19:30

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