A power Amplifier delivers 50 W output at 50% efficiency. The ambient temperature is 25$$^\circ $$ C. if the maximum allowable junction temperature is 150 $$^\circ $$ C, then the maximum thermal resistance $${\theta _{Jc}}$$ that can be tolerated is

The circuit shown, the figure supplies power to on 8 v speaker or L.S. The vaLUES OF $${I_C}$$ and $${V_{CE}}$$ for this ciruit will be

To obtain very high input and output impedances in a feedback Amplifier, the mostly used is

An op-Amp is used as a zero-crossing detector. If maximum output available from the Op-Amp is $$ \pm 12\,\,{V_{p - p}}$$ and the slew rate of the Op-Amp is 12 $$V/\mu $$ sec then the maximum frequency of the input signal that can be applied without causing a reduction in the P-P output is _____