The way I like to talk about resistance and resistivity is as a forth grade class.  Imagine you are trying to get from one side of a room to another, and a group of forth graders are blocking your path.  Why forth grades? because they are like herding cats they don't stay organized and if left only for any period of time, the would wander about the room.  Truth is they would have great deal more inertia then i would but adults tend to organize and are not a good representative of what is going on in the wire.  

    Resitivity is a representation of the density and "inertia" of those forth graders.  The more dense and and higher the inertia the hard it is to move from one point of the room to the other.

    The length of the room also has a negative effect on resistance, the longer the room the more forth graders between me and the other side of the room 

    Width (or area if you are allow to up and down along with left and right), even though it increases the amount of forth graders it also opens up more "holes" in the wire allowing the charge to move forward.  Think of it this way, a wider circuit allows for more pathways for the charge to move through, which lowers the resistance. 

    Temperature is the last thing to consider when determining resistance.  Remember that temperature is an expression of the amount of kinematic energy 

 What is an Ohm

     A unit of electrical resistance equal to that of a conductor in which a current of one ampere is produced by a potential of one volt across its terminals. 

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