Explanation: When external weight is applied to the platform. One pair of element elongate and the other pair compresses. Therefore, RT1 and RT3 is △R and the increase in RT2 and RT4 is also by △R. 9. The gain of the differential amplifier is -125. Assume the voltage applied to bridge circuit Vdc=+10v and the unstrained resistance of four element of strain gage is 200Ω. When a certain weight is placed on the platform, the output voltage Vo=5v. Determine the change in resistance of each strain gage for analog weight scale. (Assuming the output is initially nulled).
A. 1Ω
B. 0.8Ω
C. 0.3Ω
D. 1.83Ω
Answer:A
Explanation: When external weight is applied to the platform. One pair of element elongate and the other pair compresses. Therefore, RT1 and RT3 is △R and the increase in RT2 and RT4 is also by △R. 9. The gain of the differential amplifier is -125. Assume the voltage applied to bridge circuit Vdc=+10v and the unstrained resistance of four element of strain gage is 200Ω. When a certain weight is placed on the platform, the output voltage Vo=5v. Determine the change in resistance of each strain gage for analog weight scale. (Assuming the output is initially nulled).
A. 1Ω B. 0.8Ω C. 0.3Ω D. 1.83Ω
Explanation: The output voltage of analog weight scale, Vo = Vdc×(△R/R)×(RF/R1)