In the transistor amplifier shown in figure, the ratio of small signal voltage gain when the emitter resistor is bypassed by the capacitor $$'{C_e}'$$ to when it is not bypassed. (Assuming of simplified approximate $$h$$- parameter model for transistor) is

The depletion region (or) space charge region (or) transition region in a semiconductor $$p-n$$ junction diode has

A non inverting op - amp amplifier is shown in figure. The o/p voltage is

Let the magnitude of the gain in the inverting op - amp amplifier circuit shown be $$x$$ with switch $${S_1}$$ open. When the switch $${S_1}$$ is closed, the magnitude of gain becomes.