Imagine you are late to school/college/work, and to reach your destination you do want to pass through a crowded place. You have to spend more energy to push others and run. So instead of a smooth motion you needed to spend your energy to reach your destination.
Similarly when a potential difference is applied across a conductor electrons move and collides with the atoms and electrons vibrating in its path.It has to spend more energy which is lost as heat.This is resistance to its motion. In mechanics it is similar to friction.
The expression for resistance by ohm's law: R=V/I (V-voltage I - current)
At lower temperatures, the vibrations of these atoms reduces hence offers very low resistance.This is known as super conductance. These conditions are achieved at very low temperatures i.e at aprrox. 4 Kelvin(-270 degree celsius)
by electric, i suppose you mean electricity. in simple words, electricity is the energy constituted by the flow of electrons in a particular direction. so resistance is the opposition offered to the flow of current. different materials show different magnitudes of resistance. for example, metals like Ag and Cu show minimum resistance and maximum conductance where as Si and Ge show intermediate resistance and insulators show very high resistance.
however, if this is still not easy to understand for you, let us try another way. take for example the case of a ball sliding on floor. if the floor is polished, the ball will move smoothly. but if the surface is rough, the ball will move slowly due to friction. here friction is the opposition to the movement of the ball. not consider electrons moving in the wire. they move in the same manner as this ball and the opposition the material of wire offers to their movement it called resistance.
scientifically, it is represented as the ratio of potential difference(V) to the current(I).
R=V/I
Hope this helps you to understand. :)
resistance this is a necessary ingredient in the electrical circuits for simple explanation i think you know how to ride a bike .let us consider the bike ,if we encounter a speed breaker then we apply brakes and make our bike slow down . consider the bike as electron and resistor as speed breaker and the speed as the voltage . now as the current with certain voltage pass through a resistor it resists current (i.e. the conductance decreases in the resistor compared to the metal conductor wire as result of opposing it electrons gets some amount of energy wasted in the form of voltage drop )as its conductance is less .i think this might help to solve your doubt
Refer the below link for more information about the resistance.
http://searchcio-midmarket.techtarget.co...
the resistance R of a conponent is defined as the ratio of the potential difference V across it, to the current I flowing through it
Resistance is the oppostion to the flow of electrons.
ohms law, current = voltage/resistance
to understand more lets take below water pipe for example.
pipe width = resistance
amount of water flowing=voltage
speed at which it is flowing = current
so accoding to ohms law pipewidth(resistance) directly propotional to amont of water(voltage) and inversly proportional to speed of water flow(current)
so more the resistance, more voltage & less current
__________
)__________) --> water
