neither is better, it depends on purpose
BJT is nothing but the addition of two PN junction diodes. There are two types of BJT= P-N-P or N-P-N P-N N-P + or + N-P = P-N-P P-N =N-P-N SCR is a thyristor which is made adding two BJTs. Of course they are made of sillicon. Exempli gratia: P-N-P + + N-P-N = P-N-P-N comparison between scr bjt and mosfet Check the related link for further information.
It depends on the exact part numbers, but power devices are typically slower. There are, of course, RF power transistors, so you have to compare apples with apples.
Yes
The conduction angle in an SCR is the phase angle relative to the power line at which point the gate is fired to commit the anode to conduct to the cathode. By varying the conduction angle, you can change the average power transferred by the SCR.
thyristor can be scr or triac scr is strictly dc a triac is back to back scr's with a common gate two scr's back to back can be gated independently scrs cost less than triacs an scr can be combined with a full wave bridge to make an equivalent to a triac but this gives an additional 1.5V forward voltage drop
it is the collector voltage multiplied by the sum of all the currents.
Disadvantage:Easy to damage when compared to BJT
One way is to use a microcontroller with an output pen set up with hardware PWM into the scr, the scr then controls the heating element of the hotplate. A thermistor can be added for a control feedback loop.
Bipolar junction transistor(BJT)
The firing angle of a Silicon Controlled Rectifier (SCR) is the angle (in degrees) in the AC cycle at which the SCR is triggered to conduct. It determines the point in the waveform where the SCR is turned on, thereby controlling the amount of power delivered to a load. A lower firing angle results in higher output voltage and power, while a higher firing angle reduces both. This parameter is crucial in applications like phase control in light dimmers and motor speed controls.
because it is gcr not scr
The SCR's gate electrode is used to turn the SCR on, i.e. fire it.