What dose it mean to say that a force is a vector?

A force is a vector quantity. As learned in an earlier unit, a vector quantity is a quantity that has both magnitude and direction. ... Because a force is a vector that has a direction, it is common to represent forces using diagrams in which a force is represented by an arrow.

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2

conservation of mass

mass before something happens = mass afterwards