Explain why a single fixed pulley is used despite no gain in mechanical advantage.

Explanation

### Step-by-Step Solution:

1. **Understanding the Fixed Pulley**: A single fixed pulley consists of a wheel that is fixed in place, with a rope that runs over it. The load is attached to one end of the rope, while the other end is where the effort is applied.

2. **Mechanical Advantage**: Mechanical advantage is defined as the ratio of the load force to the effort force. In the case of a single fixed pulley, the mechanical advantage is 1, meaning that the effort applied is equal to the load being lifted. This means there is no gain in mechanical advantage.

3. **Purpose of a Fixed Pulley**: Despite having no mechanical advantage, a single fixed pulley is used primarily to change the direction of the applied force. This allows the user to pull down on the rope instead of lifting the load directly upwards.

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