Physics Chapter 7: Circuits and Magnetism

Question 1

The dielectric constant

Answer 1

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)

Question 2

A greater dielectric constant means that a capacitor can store _________ charge at a given voltage

Answer 2

More

Question 3

What does a greater dielectric constant imply for a capacitor?

Answer 3

A capacitor can store more charge at a given voltage

A higher dielectric constant enhances the capacitor’s ability to store charge.

Question 4

What is the relationship between capacitance (C) and dielectric constant (k)?

Answer 4

Capacitance increases proportionally to the dielectric constant

This means that materials with greater dielectric constants lead to higher capacitance.

Question 5

What is the formula that relates capacitance (C) and dielectric constant (k)?

Answer 5

C’ = k * C

C’ is the modified capacitance, and C is the capacitance under vacuum conditions.

Question 6

Fill in the blank: A higher dielectric constant _________ the capacitance of a capacitor.

Answer 6

capacitance

Question 7

True or False: The capacitance of a capacitor is linearly proportional to the dielectric constant.

Answer 7

True

Question 8

What does C represent in the context of capacitors?

Answer 8

Capacitance under vacuum conditions

C is the baseline capacitance used for comparison with modified capacitance.

Question 9

What does C’ indicate in the equation C’ = k * C?

Answer 9

Modified capacitance

Question 10

What are all the variables?

Answer 10

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.

Question 11

Difference between paramagnetics vs diamagnetics

Answer 11

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.

Question 12

What is current

Answer 12

Charge over time 1A = C/s

Question 13

Power dissipated by a resistor equations

Answer 13

Question 14

Voltage is a measure of

Answer 14

Difference in potential energy. Charges spontaneously flow across voltage differentials

Question 15

Voltage differentials are sometimes called electromotive force. Why is electromotive force (emf) misleading?

Answer 15

Because voltage is NOT a force. Voltage is like potential energy

Question 16

Formula for resistance

Answer 16

Question 17

Ohms law

Answer 17

V = IR

Question 18

Units for voltage

Answer 18

Volts (J/C)

Question 19

Units for ohms

Answer 19

Ohm (J*s/C^2)

Question 20

Formula for conductance

Answer 20

Question 21

Kirchhoff’s Law

Answer 21

Question 22

Formula for I, V and R for series circuits

Answer 22

Question 23

Formula for I, R and V for parallel circuits

Answer 23

Question 24

Dielectric material

Answer 24

Insulating material between conductive plates. Greater capacitance with more insulation

Question 25

Most important equation related to capacitance

Answer 25

Question 26

Capacitance is measured in

Answer 26

Farads

Question 27

Capacitances create

Answer 27

Uniform electric fields E = V/d

Question 28

Capacitors can store potential energy by the equation

Answer 28

Question 29

Equation for total capacitors in series vs parallel

Answer 29

Question 30

Magnetic field strength formula

Answer 30

u = permeability of free space

Question 31

Right hand rule

Answer 31

Thumb = direction of current Fingers = magnetic field Palm = magnetic force

Question 32

Formula for magnetic field force on a single charge

Answer 32

Question 33

Radius of circular motion of a charged particle in a uniform electric field

Answer 33

Question 34

Magnetic force on a current

Answer 34

Question 35

Magnetic force on a current

Answer 35

Question 36

Equation for capacitance relating charge and voltage

Answer 36

C = Q/V. Amount of charge stored per voltage

Question 37

Positive end of a battery (is it the long line or short?)

Answer 37

Long line

Question 38

Negative end of a battery (is it the long line or short?)

Answer 38

Short line

Question 39

what does the arrow mean

Answer 39

variable resistor

Question 40

Can dimagnets and paramagnets become permanent magnets?

Answer 40

NO Paramagnetic Materials (❌ Cannot Become Permanent Magnets) Weakly attracted to magnetic fields due to unpaired electrons. Lose all magnetization when the external field is removed (no domain alignment). Diamagnetic Materials (❌ Cannot Become Permanent Magnets). Repelled by magnetic fields because they create small opposing magnetic fields. Diamagnetism is a universal property of all materials but is usually very weak.