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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?
I 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.
Power = Force v Speed
Power of my horse = 104kgx9.81m/s^2 x 0.732m/s = 1HP =746W
Force/tension in rope stay the same if horse run at 0.73m/s or at 15m/s, so why then horse need to be more powerfull to pull at higher speed even if backward force at him(rope tension) stay the same?
I understand that if I increase weight, it is hrader for horse to pull at higher speed because now is backward force increased, but don't understand why is harder to pull at higher speed if weight(backward force)...