Can anyone help me with this quetion?

Given Vg=1+ 10Ig. The gate source voltage is a rectangular pulse of 15V with 20micro second duration. For an average power dissipation of 0.3W and peak gate drive power of 5W. Determine
i) Resistance to be connected series with the SCR gate.
ii)Triggering frequency
iii) The duty circle.

 

Vg=1+ 10Ig.

Not quite sure what you mean by this. But if you know the voltage on the gate and the current flowing, then you know the power dissipated. The duty cycle and frequency will depend on getting the average power down to 0.3W.

A resistor in series is used to control the gate current. You will probably have to consult the SCR datasheet to find a graph of gate forward voltage v. current.