Question No$.3$:

In a stereo amplifier circuit, there is a resistor across which you measure $25$ V $,$ and your ammeter indicates $50$ mA of current through the resistor. What is the resistor's value in kilohms? In ohms?

Question No$.4$:

a$-$ How many kilowatt$-$hours of energy are used by a $250$ W light bulb burning for $8$ h $?$

b$-$ How much does it cost to run a heater $(1322$ W $)$ for $24$ hours if energy cost is $11$ per kilowatt$-$hour?

Question No$.5$:

a$-$ What is the maximum voltage that can be applied to a $\frac{1}{4}W,100$ resistor if the power rating is not to be exceeded?

b$-$ A power supply used in the lab operates with an input power of $1$ W $.$ It can provide an output power of $750$ mW $.$ What is its efficiency?

Question No$.6$:

In Figure $6,$ how much current does ammeter $1$ indicate? Ammeter $2?$

Figure $6$

Question No$.7$:

The circuit of Figure $7$ is an adjustable voltage divider. If the potentiometer is linear, where would you set the wiper in order to get $5$ V from $B$ to A and $5$ V from $C$ to $B?$

$7$

$2$

Problem No$.8$:

For the original circuit in Figure $8,$ determine the Thevenin equivalent circuit as viewed from the output terminals A and $B.$

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