The terms speed and velocity are sometimes confused although they have different meanings.

The speed with which work is done is called power. To lift the same object to the top implies carrying out the same amount of work. To lift it at a different speed, implies using a different amount of power.

The educational resource shows a visual about the free fall in vacuum: whatever their shape and mass, all bodies fall with the same speed in a vacuum.

Concep of doppler effect.

Didactic unit about Rectilinear Movement for 4th year of compulsory secondary education. Uniform Movement (I). Uniform Movement (II). Uniformly Accelerated Motion (I). Uniformly Accelerated Motion (II).