Select the best answer to make statements 21 through 52 true, and place the corresponding letter

Select the best answer to make statements 21 through 52...

Key Concepts

Ohmmeter Operation

An ohmmeter is an instrument used to measure the resistance between two points in a circuit. It works by applying a small voltage and measuring the current that flows to calculate resistance. In circuit analysis, understanding how an ohmmeter works is crucial to diagnosing circuit issues, such as identifying whether components are functioning properly or if there are unwanted connections like shorts.

Short Circuit

A short circuit occurs when two points in a circuit that are supposed to be at different potentials are directly connected by a low resistance path, often resulting in a reading of zero resistance. Recognizing the presence of a short circuit is important because it can alter the normal operation of a circuit, bypass components, and potentially cause hazardous conditions if left unresolved.

Open Circuit

An open circuit means that there is a break or interruption in the path through which current flows, resulting in infinite or very high resistance. This is the opposite of a short circuit and is critical to understand in circuit analysis since open circuits prevent current flow and can lead to non-functioning components or systems.

Circuit Analysis and Fault Diagnosis

Analyzing a circuit involves understanding the arrangement of components in series, parallel, or a combination of both, and how these configurations affect overall circuit behavior. In fault diagnosis, measurements such as resistance readings help pinpoint issues like shorted or open components by comparing expected versus actual values, thereby guiding repairs or modifications.

Transcript

00:01 So if we simplify the circuit diagram which is here we get something like this where the 12 oms and 22 oms resistor are in series are in parallel and then 4 .5 ombs register is in series with these two guys and then this whole setup is in parallel connection with 14 oms and let's let's actually call this setup r1 so that it's easier to calculate now the first job for us is to find out this r1 2 value so it's going to be r1 2 which is equal to 1 over 12 oms plus 1 over 22 oms reciprocal of that and that gives us 7 .7 6 5 oms now since this guy is in series connection with 4 .5 so the total and then let's call this guy r3 so the total equivalent resistance will be r1 to 3 which is 4 .5 plus 7 .765 oms which is equal to 12.

01:42 265 oms let's actually make some space here so yeah so now we know this and from there we know that 14 oms is in parallel connection with this whole setup so that's going to be our eq which is parallel so that's going to be one point one over one two six five oh so that's this guy plus one over 14 oms reciprocal of that and that gives us and that gives us 6 .538 oms let me actually represent it properly so that we can understand so now this whole setup we call this r one two three right so that's the equivalent resistance of the whole circuit now for part b we need to find the current that's going through this resistor for denome so what we can do is we can apply kirchups loop rule on this loop and if we do so we see it's going to be shy minus i 1 4 times r14 so i 1 4 is basically the current that's passing to 14 -homes resistor so if we solve for i 1 4 we get something like this and here our emm voltage or shy is given so that's that's how we get our current so now we know that 0 .4286 amps current is going through this part so we need to figure out what amount of current is going through we need to figure out what amount of current is going through r12 and r12 to be precise so what we do here is again we are using kirchap's law loop rule for the outer loop and by outer loop we mean that we take this whole thing and we're considering these two resistor as one.

04:39 So that means instead of writing these two separately, we're writing r1 ,2.

04:45 So that means the current, so that means this guy and this whole thing is in series connection.

04:50 So the current flowing through the setup will be same.

04:55 So that's what we did here...

Please give Ace some feedback