MIDTERM $1$

Date : ${18}^{th}$ October $2024$

Q$1(35$ pts $)$

$\backslash$table$[[$Color$,1.$ Band,$2.$ Band,$3.$ Band Multiplier,$4.$ Band Tolerance$],[$black$,-,0,1,-],[$brown$,1,1,10,+1-1\%],[$red$,2,2,100,+1-2\%],[$orange$,3,3,1000,-],[$yellow$,4,4,10000,-],[$green$,5,5,100\text{'}000,-],[$blue$,6,6,11000\text{'}000,-],[$purple$,7,7,-,-],[$grey$,8,8,-,-],[$white$,9,9,-,-],[$gold$,-,-,0\mathrm{.}1,+1-5\%],[$siver$,-,-,0\mathrm{.}01,+/-10\%]]$

a$)$ Colors on two resistances coded in $4$ band system are as follows.

Red Gray Black gold

Res Green Green silver

Calculate their value and the range of values they may take in practice.

b$)$ A $1\mathrm{.}5$ volt battery is moving $15{10}^{18}$ electrons between its terminals. Determine the energy expended in this process.

Note: $1$C is $6\mathrm{.}242{10}^{18}$ electrons

c$)$ You have a $12V,60Ah$ car battery. This battery is fully charged. When your engine starts it draws $200$ A for $15$ seconds. You try to start your engine $6$ times, each time takes $15$ seconds. How much $Ah$ is left on the battery?

d$)$ Show the schematic diagram of an ideal and non$-$ideal voltage source.

A non$-$ideal $50$ V DC voltage source has $0\mathrm{.}2$ ohm internal resistance. What is its terminal voltage when no load is connected to its terminals?

Now a $5$ ohm load resistance is connected to this battery. Draw the circuit diagram. What is the voltage at the terminals of the battery now?

What is the power drawn from the source? What is the power spent on the load? What is the efficiency of this operation?