Friction on a dry marble floor is _____ than that on a wet marble floor.

Explanation

To solve the question "Friction on a dry marble floor is _____ than that on a wet marble floor," we can follow these steps:

### Step 1: Understand the surfaces
- **Dry Marble Floor**: The surface is rough with many grooves and irregularities.
- **Wet Marble Floor**: The surface becomes smoother as water fills in the grooves and irregularities.

### Step 2: Analyze the effect of surface texture on friction
- According to the old theory of friction, a rough surface provides more friction because the irregularities can grip onto objects better.
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