Consider an amplifier circuit using a transistor.The output power is several times greater than the input power.Where does the extra power come from?

In a common emitter amplifier circuit using a n-p-n transistor, the phase difference between the input and the output voltages will be ……..

The output power in step-up transformer used in practice is …..

A circular coil of radius 8.0 cm and 20 turns is rotated about its vertical diameter with an angular speed of 50 rad s^(-1) in a uniform horizontal magnetic field of magnitude 3.0 xx 10^(-2) T. Obtain the maximum and average emf induced in the coil. If the coil forms a closed loop of resistance 10 Omega , calculate the maximum value of current in the coil. Calculate the average power loss due to Joule heating. Where does this power come from ?

In a CE transistor amplifier there is a current and voltage gain associated with the circuit. In other words there is a power gain. Considering power a measure of energy, does the circuit violate conservation of energy?

For circuits used for transporting electric power, a low power factor implies large power loss in transmission. Explain.

Consider the circuit arrangement shown in figure (1) for studying input and output characteristics of n-p-n transistor in CE configuration. Select the values of R_(B) and R_(C ) for a transistor whose V_(BE)=0.7V , so that the transistor is operating at point Q as shown in the characteristics shown in figure (2). Given that the input impedance of the transistor is very small and V_(C C)=V_(BB)=16V , also find the voltage gain and power gain of circuit making appropriate assumptions.

A transistor has a current amplification factor (current gain) of 50 , In a CE amplifier circuit, the collector resistance is chosen as 5 k Omega and the input resistance is 1 k Omega Calculate the output voltage if input voltage is 0.01 V.

(a) For circuits used for transporting electric power, a low power factor implies large power loss in transmission. Explain. (b) Power factor can often be improved by the use of a capacitor of appropriate capacitance in the circuit. Explain.

A common emitter circuit is used as an amplifier, its current gain is 50. if input resistance is 1kOmega and input voltage is 5 volt then output current will be

A nuclear power supplying electrical power to a villages uses a radioactive material of half life T year as the fuel . The amount of fuel at the beginning is such that the total power requirement of the village is 12.5% of the electrical power available from the plant at that time. If the plant is able to meet the total power needs of the village for a maximum period of n T years , then the value of n is