Force is push or pull.
Unbalanced forces make an object accelerate.
The unit of force is the Newton (abbreviation is N).
A Newton is the force it takes to make 1 kg change its velocity by 1 m/s (meter per second) every second.
Which can be written:
1 N = 1 kg m/s2 (kilogram meter per second squared)
![kicking a ball](../physics/images/ball-kick.jpg)
See: Acceleration