The difference between "roll" and "turn" lies in the axis of rotation. "Turn" rotates an object around its vertical axis, changing its facing direction, while "roll" rotates it around its forward-to-back axis, affecting its side-to-side orientation.
Here's a more detailed breakdown:
-
Turn:
- Axis of Rotation: Vertical axis (imagine a line running straight up and down through the object).
- Effect: Changes the object's orientation in a horizontal plane. It alters the direction the object is facing (e.g., turning a car to the left or right). The position of the object does not change in place but it will be facing a different direction.
- Example: Steering a car, a dancer pirouetting, rotating a map.
-
Roll:
- Axis of Rotation: Forward-to-back axis (imagine a line running from the front to the back of the object).
- Effect: Tilts the object to the side. Think of an airplane banking during a turn or a ship rocking in the waves. The object's position is less significantly changed, but its orientation relative to the ground is.
- Example: An airplane banking, a ship rocking, a barrel rolling down a hill.
| Feature | Turn | Roll |
|---|---|---|
| Axis of Rotation | Vertical | Forward-to-back |
| Primary Effect | Changes facing direction (horizontal orientation) | Tilts the object to the side (side-to-side orientation) |
| Example | Steering a car, a spinning top (primarily if viewed from above) | An airplane banking, a log rolling. |
In simpler terms, think about holding a can of soda. To turn it, you'd rotate it like a lazy susan, changing what label is facing forward. To roll it, you'd tilt it from side to side.
