Sliding friction is weaker than _____

Options

A. Static friction
B. rolling friction
C. fluid friction
D. None of them

Answer

To solve the question "Sliding friction is weaker than _____", we need to analyze the types of friction.

### Step-by-Step Solution:

**Step 1: Understand the Types of Friction**
- Friction is the resistance that one surface or object encounters when moving over another. There are several types of friction, including static friction, sliding (kinetic) friction, and rolling friction.

**Step 2: Compare Sliding Friction and Rolling Friction**
- Sliding friction, also known as kinetic friction, occurs when two surfaces slide past each other. It is generally stronger than rolling friction.
- Rolling friction occurs when an object rolls over a surface. This type of friction is usually weaker than sliding friction because the point of contact between the rolling object and the surface changes continuously.

**Step 3: Conclude the Comparison**
- Since rolling friction is weaker than sliding friction, we can conclude that sliding friction is weaker than static friction (which is the friction that must be overcome to start moving an object at rest).

### Final Answer:
Sliding friction is weaker than **static friction**.

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