Module 4 Physics Flashcards

Define Ohm’s Law

Ohm’s Law describes how voltage is proportional to current where the constant of proportionality is resistance

Define Ohmic Resistors

Ohmic resistors are materials which have a constant resistance regardless of the amount of current passing through them or the voltage applied across them

Define Non-Ohmic Resistors

Non-Ohmic resistors are materials which have a resistance that is dependant on the amount of current passing through them or the voltage applied across them

Define a conductor

A conductor is a substance that contains charged particles which are free to move throughout the substance

Define an insulator

An insulator is a substance that does not contain charged particles which are free to move

Define resistance

Resistance refers to how much opposition to electron flow a particular conductor has

Define Kirchoff’s Voltage Law

Kirchoff’s Voltage Law states that in any closed loop, the sum of all voltages is 0

Define Kirchoff’s Current Law

Kirchoff’s Current Law states that the total current into a junction is equal to the total current out of the junction

Explain what happens to resistance when you increase temperature

By increasing the temperature, the cations in the metallic lattice of the wire would have a higher vibrational kinetic energy. As the cations oscillate about their rest position at a greater amplitude, the likelihood that an electron collides with another particle increases, and thus the resistance increases.

Explain what happens to the resistance when the length of the conductor increases

Resistance is due to the collisions between electrons and another particle in the substance (such as other electrons, impurities or cations in the metallic lattice). As the distance an electron has to travel increases, the likelihood of an electron colliding with another particle increases, and thus the resistance of the conductor increases

Explain what happens to the resistance when cross sectional area of the conductor increases

By increasing the cross sectional area of the conductor, the likelihood an electron collides with another particle decreases, and thus the resistance of the conductor decreases