Question

At what inclination to the ground are soil thermometers installed in the observatory?

• A. 30 degrees
• B. 45 degrees
• C. 60 degrees
• D. 90 degrees

Hint:

Soil thermometers: Planted vertically (90°) to measure temperature at specific soil depths.

Answer 1

The Correct Option is D

Step 1: Soil thermometers must read the temperature at an exact depth directly below a surface point.
Step 2: A slanted installation at 30, 45 or 60 degrees would place the bulb off to the side, not at the true depth.
Step 3: Only a vertical, 90 degree installation keeps the bulb exactly below the marked depth.
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