Resistance measurement using multimeter

Status
Not open for further replies.

vinodquilon

Full Member level 3
Joined
Oct 24, 2009
Messages
158
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,298
Visit site
Activity points
2,558
Resistance/Voltage measurement using multimeter

Consider the below circuit with 28V supply and 5A load.

What voltage would I expect when I connect a multimeter between A & B ?
V(AB1)= V(R6)+V(R8)+V(R9)


What voltage would I expect when I connect a multimeter between C & D ?
V(CD1)= V(R7)+V(R8)+V(R10)

Consider the second circuit.

What voltage would I expect when I connect a multimeter between A & B ?
V(AB2)= V(R6)+V(R8)+V(R9)


What voltage would I expect when I connect a multimeter between C & D ?
V(CD2)= V(R8)

Am I right ? And V(AB2)>V(AB1)
 

Attachments

  • Rsistance.jpg
    59.9 KB · Views: 91
Last edited:

Many multimeters work by injecting a small current and
reading a voltage. A circuit with current already flowing
will jack that reading because the total current is not
what the injected current and its corrolary, assumed
scale factor are. If you're trying to measure resistance
using the resistance function.

In such a case, you would need to know the meter
scale factor & current to determine what the response
to some different current (sum) will be on a given
resistance.

Now if you're just using the voltage scale and an assumed
branch current, then "it is what it is" - "what it is", being the
likely point of the homework assignment.
 
The exercise problem isn't completely clear though.
- Each resistor has an arbitrary different value, calculate the differential voltages in general form
- All resistors are equal
 

FvM said:
The exercise problem isn't completely clear though.
- Each resistor has an arbitrary different value, calculate the differential voltages in general form
- All resistors are equal
Click to expand...
All are different resistors. The aim is to calculate voltage not resistance.
 
Last edited:

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…