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phymath7
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- Why post office box can't be used to measure high or low resistance?
Why meter bridge is chosen over post office box to measure low resistance?
Undergrad Measuring Low Resistance: Why Meter Bridge is the Preferred Choice
- Thread starter phymath7
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The meter bridge is preferred over the post office box for measuring low resistance due to its superior sensitivity and accuracy. The post office box, which operates as a Wheatstone bridge, is limited in its measurement range and primarily used for identifying short circuits rather than measuring resistance. Its design does not effectively utilize the meter's sensitivity because it is affected by the bridge components. Additionally, the meter bridge allows for a more precise measurement technique by enabling current to pass through the meter for full-scale deflection before measuring the voltage drop across an unknown low resistance. Overall, the meter bridge is more effective for low resistance measurements compared to the post office box.
As you can see from the picture, i have an uneven U-shaped tube, sealed at the short end. I fill the tube with water and i seal it. So the short side is filled with water and the long side ends up containg water and trapped air.
Now the tube is sealed on both sides and i turn it in such a way that the traped air moves at the short side.
Are my claims about pressure in senarios A & B correct?
What is the pressure for all points in senario C?
(My question is basically coming from watching...