Question

Match the device with its working principle:
 

List-1	List-2
a. Bourdon gauge	V. Deformation of element
b. Pirani gauge	I. Thermal conductivity
c. Semiconductor strain gauge	III. Piezo resistive effect
d. Bi-metallic strip	II. Thermal coefficient of expansion

• A. a–V, b–I, c–II, d–III
• B. a–V, b–II, c–III, d–I
• C. a–V, b–I, c–III, d–II
• D. a–V, b–III, c–I, d–II

Hint:

Always associate deformation with mechanical sensors, thermal conductivity with Pirani gauges, and piezo resistive/electric effects with strain or vibration-based sensors.

Answer 1

The Correct Option is C

Let’s match each item: - **a. Bourdon gauge** works on **mechanical deformation of an elastic element** due to pressure → **V** (Deformation of element)
- **b. Pirani gauge** works on **change in thermal conductivity** of gases → **I** (Thermal conductivity)
- **c. Semiconductor strain gauge** uses the **piezo resistive effect**, where resistance changes due to strain → **III** (Piezo resistive effect)
- **d. Bi-metallic strip** bends due to **different thermal expansion** of two bonded metals → **II** (Thermal coefficient of expansion)