science test Flashcards
what is a fluid
a substance that has no fixed shape and is free to flow, such as liquids and gases.
what is viscosity
refers to a fluids thickness or resistance to flow
what are the factors that affect viscosity
cohesion, adhesion
cohesion
the force of attraction between the particles of a substance. fluids with slow flow rates have particles with greater cohesion (they stick together and would be considered viscous)
adhesion
the force of attraction between particles of a fluid and particles of other substances.
causes gases and liquids to travel faster near the centre of pipes/tubes than at the edges.
the fluids attraction to the other material slows down the flow of the fluid.
particle theory of matter
helps explain why fluids act the way they day
what are the 5 points of the particle theory of matter
-all matter is made up of tiny particles
-particles have empty space between them
-particles are moving randomly all the time
-particles move fast and spread farther apart when heated
-particles attract each other
solids
-particles are tightly packed together
-have a definite shape and volume
-very strong force of attraction
liquids
-particles are farther apart than solids
-has a definite volume
-force of attraction is strong enough to hold it together
gases
-particles are much farther apart
-has no definite shape or volume
-force of attraction is very small
flow rate
measures the volume of a fluid moving past a certain point in a certain amount of time
factors that affect flow rate
-type of fluid that’s flowing
-force pushing on the fluid
-type of surface it’s flowing over
-size of opening it’s going through
mass
the amount of matter in an object or substance
volume
the amount of space an object of substance takes up
density
a measure of how much matter is in a certain volume
