Representative study notes: motion and forces
Original editorial fixture by Memorizite, 13 October 2026. Not a generated output or a completed product benchmark.

Distance is the total path length travelled. Displacement describes the change in position and includes direction. An object can travel a nonzero distance and finish with zero displacement if it returns to its starting position. In a simple out-and-back example, walking 3 metres east and then 3 metres west gives a distance of 6 metres and a displacement of zero.

Average speed is total distance divided by elapsed time. A student covering 12 metres in 4 seconds has an average speed of 3 metres per second. This does not establish that the student's instantaneous speed was constant throughout the journey.

Velocity is a vector quantity with magnitude and direction. Acceleration is the rate of change of velocity. A change in direction can therefore involve acceleration even when speed stays constant. Describing only the size of a velocity omits part of its meaning.

For constant mass in an inertial reference frame, resultant force equals mass times acceleration. A resultant force of 6 newtons acting on a 2 kilogram object gives an acceleration of 3 metres per second squared in the force's direction. Zero resultant force implies zero acceleration in this model; it does not require zero velocity.

Evaluation checks: preserve conditions and units; distinguish distance from displacement and speed from velocity; do not infer constant instantaneous speed from an average; do not replace resultant force with an unspecified individual force.