exam revision Flashcards
(27 cards)
what is inertia ?
The tendency of a body to resist a change in motion or rest.
crumple zones
The area of a vehicle that is designed to crush or crumple upon impact. Often located in the front of a vehicle.
velocity
the speed of something in a given direction
what is a contact force & examples
Contact forces are forces that require direct physical contact between two objects. Examples of contact forces include friction, tension, and air resistance.
what is a non contact force & examples
Gravitational force, Electrostatic force, Magnetic forces. They are non-contact forces because they can influence the objects without being in contact.
what is air resistance
The force acting on an object that is moving through air flowing in the opposite direction.
what is gravity
A force which tries to pull two objects toward each other.
what is a force
a push, pull or twist
what is friction
The force felt between two surfaces when one attempts to slide against the other — whether they are moving.
what is a mixture
A physical combination of two or more substances
what is a solution
A type of mixture involving two or more substances.
what is a colloid
A mixture of particles smaller than those found in a suspension but bigger than those found in a solute
what is a suspension
mixture where solid particles do not dissolve in a liquid solution
what is a sediment
When the soluble substance falls to the bottom of the mixture
what is an emulsion
A liquid dispersed in a liquid eg. Milk
what does it mean when a solution is saturated
A physical or chemical situation where a system can take no more of a substance.
what does it mean when a solution it concentrated
The amount of a substance, such as a salt, that is in a certain amount of tissue or liquid, such as blood.
what does it mean when a solution is diluted
The process of decreasing the concentration of a solute in a solution, usually simply by mixing with more solvent.
what is density
how tightly a material is packed together
what is qualitative & example
using words to describe your observations eg. big dog
what is quantitive & example
using numbers to describe your observations eg. 24 ducks
what is an inference & when do u use it
An inference is when you draw a conclusion from the evidence/experiment you have conducted. You would write an inference in your conclusion.
what is terminal velocity
is the maximum speed attainable by an object as it falls through a fluid
list one way to reduce friction
by greasing/oiling one of the surfaces touching each other
