The prompt describes the definition of average velocity and asks for its algebraic expression in terms of motion along the y-direction, using the Greek letter "Δ" (delta) to represent the change in a quantity.

The formula for average velocity is generally:

$\text{Average velocity} = \frac{\Delta y}{\Delta t}$

Where:

• $\Delta y$ represents the change in displacement (along the y-axis),
• $\Delta t$ represents the change in time.

This is the algebraic expression of average velocity, using the "Δ" notation, as typically given in physics lab manuals.

Let me know if you'd like more details or have any questions!

Here are 5 related questions that expand on this concept:

1. How is instantaneous velocity different from average velocity?
2. What is the physical significance of a negative average velocity?
3. How does the direction of displacement affect the sign of average velocity?
4. How would you compute the average velocity if given a velocity-time graph?
5. How is average speed different from average velocity?

Tip: The symbol "Δ" is widely used in physics and mathematics to represent a change or difference in quantities. Keep in mind that the direction of change matters in vector quantities like velocity.