22 Electrodynamics

Question 1

force field produced by charged object that can exert force on other charges

Answer 1

electric field

Question 2

describes how charge influences other charges around it

Answer 2

electric field

Question 3

direction of electric field (2)

Answer 3

• away from + charge
• toward - charge

Question 4

represented using electric field lines to show direction and strength

Answer 4

electric field

Question 5

formula for electric field

Answer 5

E = F/q

unit: N/C

Question 6

tells us how strong force field is at a point

Answer 6

electric field

Question 7

formula for electric field point charge

Answer 7

E = k|Q|/r^2

Question 8

field charge becomes ___ when closer to the charge; ___ as distance increases

Answer 8

stronger
weaker

Question 9

energy possessed by a charge due to its position in an electric field

Answer 9

electric potential energy (U/EPE)

Question 10

electric field can do work on the charge, causing change in its energy

Answer 10

electric potential energy (U/EPE)

Question 11

charge can gain/lose energy when it moves

Answer 11

electric potential energy (U/EPE)

Question 12

electric potential energy (U/EPE) depends on (2)

Answer 12

• charge (q)
• position in electric field

Question 13

electric potential per unit charge

Answer 13

electric potential (V)

Question 13

formula for electric potential energy (U/EPE)

Answer 13

U = q(Fd)

Question 14

describes how much energy each unit charge has at a point in the electric field

Answer 14

electric potential (V)

Question 15

electric potential (V) depends only on (2)

Answer 15

• position in electric field
• source changes

Question 16

formula for electric potential (V)

Answer 16

V = U/q

unit: J/C

Question 17

difference between F and electric field

Answer 17

F
- interaction between two charges

field
- only one charge needed to quantify

Question 18

difference in electric potential between two points

Answer 18

electric potential difference (voltage)

Question 19

represents change in EPE/U per unit charge

Answer 19

electric potential difference (voltage)

Question 20

driving force that causes charges to move in a circuit

Answer 20

electric potential difference (voltage)

Question 21

fomula for electric potential difference (voltage)

Answer 21

ΔV = Vb - Va

unit: volts (V)

Question 22

rate of flow of electric charges in a conductor

Answer 22

electric current (I)

Question 23

flows from higher potential to lower potential for positive charges

Answer 23

electric current (I)

Question 24

in metals, e- move opposite to conventional current direction

Answer 24

electric current (I)

Question 25

formula for electric current (I)

Answer 25

I = Q/t unit: ampere (A) 1A = 1C/s

Question 26

opposition to flow of I in conductor

Answer 26

resistance (R)

Question 27

resistance depends on (4)

Answer 27

- MATERIAL of conductor (conductor vs insulator) - LENGTH of conductor (longer = more R) - CROSS-SECTIONAL AREA (thicker = less R) - TEMPERATURE (more T = more R for metals)

Question 28

formula for series circuits (V, I, R)

Answer 28

I = same Rt = R1 + R2 + ... Vt = V1 + V2 + ...

Question 29

formula for parallel circuits (V, R, I)

Answer 29

V = same It = I1 + I2 + ... Rt = 1/(1/R1) + (1/R2) + ...