Video explanation
An isometric airport scene shows an aircraft moving around the runway, with a visible exhaust flame in parts of the recording. It illustrates ground motion and acceleration; the aircraft type and takeoff speed are not established by the footage.
Four principal forces
Flight involves thrust, drag, lift, and weight. During the ground roll, the landing gear still supports part of the aircraft’s weight.
Acceleration and lift
A positive net forward force accelerates the aircraft. With other conditions fixed, lift increases with the square of airspeed; angle of attack, air density, and wing configuration also matter.
Takeoff needs more than thrust
The engine primarily supplies thrust, while the wings generate lift by changing the airflow. Rotation changes angle of attack, but too much can cause a stall. A visible exhaust flame alone does not establish liftoff.