Afterwards you can explain why drag speeds up an orbiting satellite, and estimate its orbital lifetime from the density of the upper atmosphere.
Afterwards you can explain aliasing, compute the frequency a sampled signal will appear to have, and say how fast to sample to avoid it.
Afterwards you can explain why gradient descent diverges above a step size of 2/L, why it crawls in narrow valleys, even a line fit's, and how momentum helps.
Afterwards you can compute a vapor-liquid equilibrium with activity coefficients, follow a pot still with the Rayleigh equation, and explain an azeotrope.
Afterwards you can compute a room's reverberation time with Sabine's formula, measure it from a decay curve, and tell echoes, flutter, and reverberation apart.
Afterwards you can explain active noise cancellation by superposition and compute in decibels how a fixed delay limits it to low frequencies.
Afterwards you can compute the Δv of a plane change, fold it into a Hohmann burn at apogee, and explain why GEO launch sites sit near the equator.
Afterwards you can explain a gravity assist as a turn of the velocity in the planet's frame, and compute the Sun-frame speed it adds and the planet's recoil.