SPM Physics: AHA! Hydrometer – Smart Design, Easy Marks!

A hydrometer may look simple, but every part of its design serves a purpose. In SPM Physics, this is a classic Modification → Advantage question.

Key design features:

1️⃣ Long calibrated stem
→ Wider density measurement range.
→ More density values can be measured.

2️⃣ Narrow stem
→ Wider scale spacing.
→ Easier to read small density changes.
→ More sensitive.

3️⃣ Large bulb
→ Displaces more liquid.
→ Greater upthrust.
→ Supports floating.

4️⃣ Lead shots at the bottom
→ Lower centre of gravity.
→ Hydrometer remains upright and stable.

AHA! Smart design, better measurement. Not by sight, but by INSIGHT!