the negative leg is shorter than the positive leg.
because the negative leg is shorter.
On an LED, one leg will be shorter than the other. The shorter leg is the negative polarity.
Current will only flow one way through an LED, so it has a positive leg and a negative leg. One of them is longer to signify which is which (longer is negative). The negative side also has a chamfered edge on the LED itself.
Cathode (negative) is the shortest leg and there is a flat edge on the base of the LED, and it must be connected to the negative wire or "-" connection. Anode (positive) is the longest leg, and must be connected to the positive wire or "+" connection, as electricity will only pass through a LED from positive to negative.
The long leg of the LED is the Anode. Connecting the Anode to the negative end of the dry cell would bias the LED off. It would not illuminate. It may also destroy LED.
The side of any diode that must be negative in order for the diode to conduct is the "cathode".
If you plug it it in, if it doesn't light it's the wrong way round. Although these other two are more 'conventional': -The negative wire is closest to a small flat 'spot' on the LED's base. -The longer leg is the positive wire
Anode and cathode. Anode = negative lead, cathode = positive lead.
The length of the legs. The positive leg is always longer than the negative one.
The longest leg is the positive leg of any LED.
A leg is a limb, it is neither positive or negative.