Explico Playground

What is in the course

2 parts4 chapters1.3–1.8 hours of study

Motion in the plane

Part 1 · 2 chapters35–45 min

1. Position and Coordinate Systems20–30 min

   Locate a moving point in the plane in Cartesian and polar coordinates, and read velocity and acceleration off position as time derivatives.

2. Velocity Under Constant Acceleration15 min

   Predict an object's velocity at any later time from its initial velocity and a constant acceleration.

Projectile motion

Part 2 · 2 chapters45–60 min

1. Projectile Range20–25 min

   Derive and compute the range of a projectile launched over level ground.

2. The Optimal Launch Angle25–35 min

   Show why 45 degrees maximizes a projectile's range for a fixed launch speed, and what that means for other angles.

What the engine adds

Explained symbols

Every symbol in the text and in the equations links to its definition. Point at a symbol, such as the Launch angle $\explain{motion.launch-angle}{\theta}$, to open its explanation. Click the symbol to keep the explanation open. This also works for a symbol inside the formula of another explanation.

Interactive figures

Move a slider to change the launch speed or the launch angle. The trajectory, the range, and the numbers in the rendered equation change at the same time.

Sources, numbers, and checks

Claims link to their sources. Equations, tables, and figures are numbered, and a reference to one of them works across chapters: point at Table 2.1.1 to see the table. Each chapter ends with a knowledge check.

This is a small demonstration course for the explico engine, not a complete physics course.