Science Work

unit 19:gravitational and frictional force
Gravitational force
Gravitational force is a forcethat can act at a distance from an object.Gravitational force is the force of attraction between things and the earth.
Effects:gravitational force is acting on us and all other objects all the time.It is because of gravitational force that we are able to stand on the ground and not float away.Gravitational force also has many other effects.

Weight and Mass
simalirity:Both can be measured.
differences:-Weight:weight is a force.the gravitational force acting on an object.different at different places.the weight of an object is different on the earth,the moon and other planets.-Mass:mass is not a force.the amount of matter in an object.constant.the mass of an object is the same,regardless of where the object is.

Frictional force
Frictional force is a force that opposes motion.It is produced when two surfaces rub against each other.
Effects:-slow down and stop moving effect
-Prevent an object from starting to move.
-affect the movement of objects on different surfaces.