Question

Which type of strain gage has better resolution?

(a) Semiconductor strain gage

(b) Wire strain gage

(c) Wire and Semiconductor strain gage

(d) None of the mentioned

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This is a very interesting question from Instrumentation Amplifier topic in section Operational Amplifier Applications of Linear Integrated Circuits

Answer 1

The correct answer is:

(a) Semiconductor strain gauge

Explanation:

Semiconductor strain gauges have better resolution compared to other types, such as wire strain gauges, due to the following reasons:

1. Higher Gauge Factor: Semiconductor strain gauges have a much higher gauge factor (50 to 200) compared to wire strain gauges (typically 2 to 5). The gauge factor indicates the sensitivity of the strain gauge to strain.

   • A higher gauge factor means that a small strain will produce a larger change in resistance, leading to better resolution and sensitivity.

2. Non-linearity Advantage: While semiconductor strain gauges are more nonlinear than wire gauges, they excel in applications requiring high precision and resolution for detecting small strains.

3. Smaller Size: Semiconductor strain gauges are smaller, which allows them to measure strain more precisely in localized areas.

Why not the other options?

• Wire strain gauge: These are robust and widely used but have a lower gauge factor and resolution compared to semiconductor gauges.
• Wire and Semiconductor strain gauge: This option does not apply since their resolution characteristics differ.
• None of the mentioned: Incorrect, as the semiconductor strain gauge clearly provides better resolution.