A Brief Look at the Force of Drag using Numerical Modeling (or The Euler Method)

The video tutorial introduces the concept of air resistance and its impact on projectile motion. It explains how air resistance affects the forces acting on an object, specifically a lacrosse ball, and how to calculate these forces using the drag equation. The tutorial then introduces numerical modeling through the Euler method to solve differential equations, demonstrating how to use Excel for these calculations. The video concludes by comparing the displacement of the ball with and without air resistance, proving the initial statement about air resistance's effect.

What is the primary reason an object is not in projectile motion when air resistance is considered?

• The acceleration in the Y direction is constant.

• The object moves in a vacuum.

• The acceleration in the Y direction is no longer -9.81 m/s².

• The velocity in the X direction remains unchanged.

Which force acts opposite to the direction of velocity on a projectile?

• Drag force

• Normal force

• Gravitational force

• Tension force

What is the drag coefficient of a smooth sphere, such as a lacrosse ball, according to NASA?

• 1.0

• 0.5

• 0.7

• 0.3

How does the Euler method help in calculating the motion of a projectile?

• By using only analytical solutions.

• By assuming constant velocity throughout the motion.

• By splitting the motion into small intervals with constant acceleration.

• By ignoring the effects of drag force.

What is the initial velocity in the X direction of the ball in meters per second?

• 5.0 m/s

• 6.2 m/s

• 4.469 m/s

• 3.5 m/s

What is the significance of using an absolute reference in Excel calculations?

• It allows the cell reference to change when copied.

• It keeps the cell reference constant when copied.

• It automatically updates the formula.

• It speeds up the calculation process.

What is the approximate difference in displacement caused by drag force in the X direction?

• 9 millimeters

• 15 millimeters

• 1 millimeter

• 5 millimeters

How does the velocity in the Y direction change as the ball falls?

• It decreases in magnitude.

• It remains constant.

• It oscillates.

• It increases in magnitude.

What is the purpose of adjusting the last time value in the Excel calculations?

• To simplify the calculation process.

• To match the initial velocity with the final velocity.

• To increase the accuracy of the drag coefficient.

• To ensure the displacement in the Y direction is exactly -0.70 meters.

What can students do with the Excel file provided on the website?

• Change the drag coefficient and observe effects.

• Only view the calculations.

• Print the file without any changes.

• Delete all the data.