Current Electricity Flashcards
define electric current?
unit? define
formula? symbol?
what produces current?
the time rate of flow of electric charges through any cross-sectional area
I=Q/t Ampere
I
Potential Difference
define one ampere?
1C has how many electrons passing through it?
when 1 C of charge flows through any cross sectional area in 1 sec.
6.25x10^18 electrons
what is conventional flow of current?
why is CFOC used in problems?
- current flowing from +ve terminal to -ve terminal of a battery due to the flow of +ve charges.
- conventional current produces the same effect as the current flowing from -ve terminal to the +ve terminal due to the flow of -ve charges
materials are divided into conductors and insulators on the basis of?
example of them.
why current flows easily through conductors?
electric proprties (current flow)
c: copper silver Mg
semi: silicon germanium
i: glass and rubber
they have free charge carriers
what is potential difference?
where will be PD be produced in a circuit?
which terminal is at higher potential?
what provides PD in a circuit?
PD formula?
the diff. of EP b/w 2 points
b/w 2 ends of a conductor
+ve
battery\
the flow of current will continue as long as _________.
define 1 volt?
there is potential differnce.
when potential energy of 1 Joule is needed to move a charge of 1 Coulomb from one point to another inside the field.
what is emf?
why is it needed?
how does it happen?
explain the formula?
unit? symbol?
pg 107
what does Ohm’s law give relation of?
state it?
formula?
ohm law is applicable when?
pg 107
what is resistance?
unit? define 1 ohm?
- opposition of flow of charges
- volt per ampere called ohm
- the resistance of wire will be 1 ohm if voltage of 1 volt causes a current of 1 ampere to flow thorugh the wire.
factors affecting resistance
_____ have high resistivity.
by increasing temp. resistance of conductors _____ insulators ____ why?
insulators
what is value of resistance dependent or independent from?
most ______ show ohmic behavior?define ohmic behavior?
i: volatge current as increase in volatge increase current so ratio would be same
d: upon material, temp.,length cross sectional area
metals
in series comb. of resistors what is same and diff and why?derive it also? will the eq. resistance smaller or bigger?
trust me its easy just use your mind
pg 111
in parallel comb. of resistors what is same and diff and why?derive it also? will the eq. resistance smaller or bigger?
trust me its easy just use your mind
ohm is the unit of what?
which resistor distributes V & I?
E=?
what are electrical measuring instruments?
resistance
V: series
I: parallel
derive the unit for electrical energy?
pg 115
what does Joule’s law provides us with? state it? mathematically?
it can provide the rate at which resistance in a circuit converts EI into HE
what is electric power? formula?
SI unit of electric power? define it?
define 1 kilowatt-hour?
how many joules is it equal to?
circuit symbol for lamp, switch, heater, resistor, capacitor, fuse, earth, power supply, wires?
pg 120
use of wires, connectors, power supplies and fuse?
what is earth in a circuit?
pg 119
galvanometer?
ammeter? how does it measure? why are ammeter connected in _______?
series
