Physics Chapter 7: Circuits and Magnetism Flashcards
The dielectric constant
k = ε/ε0
Used to streamline comparisons of the dielectric properties of various substances to that of a vacuum (a ratio of its permittivity to the permittivity of free space)
A greater dielectric constant means that a capacitor can store _________ charge at a given voltage
More
What does a greater dielectric constant imply for a capacitor?
A capacitor can store more charge at a given voltage
A higher dielectric constant enhances the capacitor’s ability to store charge.
What is the relationship between capacitance (C) and dielectric constant (k)?
Capacitance increases proportionally to the dielectric constant
This means that materials with greater dielectric constants lead to higher capacitance.
What is the formula that relates capacitance (C) and dielectric constant (k)?
C’ = k * C
C’ is the modified capacitance, and C is the capacitance under vacuum conditions.
Fill in the blank: A higher dielectric constant _________ the capacitance of a capacitor.
capacitance
True or False: The capacitance of a capacitor is linearly proportional to the dielectric constant.
True
What does C represent in the context of capacitors?
Capacitance under vacuum conditions
C is the baseline capacitance used for comparison with modified capacitance.
What does C’ indicate in the equation C’ = k * C?
Modified capacitance
What are all the variables?
This formula shows how to the capacitance when not in a vacuum.
C’: Capacitance of a capacitor with a dielectric.
C: Capacitance of a capacitor without a dielectric.
k: Dielectric constant (relative permittivity).
epsilon: Absolute permittivity of the dielectric material.
epsilon_0: Permittivity of free space.
A: Area of one capacitor plate.
d: Distance between the capacitor plates.
Difference between paramagnetics vs diamagnetics
Paramagnetic substances have unpaired electrons and are attracted to a magnetic field, while diamagnetic substances have all electrons paired and are slightly repelled by a magnetic field.
What is current
Charge over time 1A = C/s
Power dissipated by a resistor equations
Voltage is a measure of
Difference in potential energy. Charges spontaneously flow across voltage differentials
Voltage differentials are sometimes called electromotive force. Why is electromotive force (emf) misleading?
Because voltage is NOT a force. Voltage is like potential energy
Formula for resistance
Ohms law
V = IR
Units for voltage
Volts (J/C)
Units for ohms
Ohm (J*s/C^2)
Formula for conductance
Kirchhoff’s Law
Formula for I, V and R for series circuits
Formula for I, R and V for parallel circuits
Dielectric material
Insulating material between conductive plates. Greater capacitance with more insulation
Most important equation related to capacitance
Capacitance is measured in
Farads
Capacitances create
Uniform electric fields E = V/d
Capacitors can store potential energy by the equation
Equation for total capacitors in series vs parallel
Magnetic field strength formula
Right hand rule
Thumb = direction of current
Fingers = magnetic field
Palm = magnetic force
Formula for magnetic field force on a single charge
Radius of circular motion of a charged particle in a uniform electric field
Magnetic force on a current
Magnetic force on a current
Equation for capacitance relating charge and voltage
C = Q/V. Amount of charge stored per voltage
Positive end of a battery (is it the long line or short?)
Long line
Negative end of a battery (is it the long line or short?)
Short line
what does the arrow mean
variable resistor
