Electrostatic Formula List

Electrostatic

  =  2 F = electrostatic force, N E = Electric field intensity / strength , NC -1 , Vm-1 Q = Charges , C

q = Charges , C

r = distance / displacement , m V = potential difference, V , JC -1 U = Electric potential energy , J ‘’can be assume as work done also’  ɛ0 = 8.85 x 10-12 F m-1 k = 1/4πɛ0 = 9 x 109 C -2 N m2

=0 =     =  =

Charge Density , C m -2

Gauss Law

 A = area , m2 Φ =Electric flux, N m 2 C -1 , V m

Capacitor

C = capacitance , F , C V -1 In air / vacuum / no dielectric

     ɛ 0 = =  =  0 = ɛ =    , −  = 0 8.85 x 10-12 F m-1

In the medium / have dielectric

ɛr = dielectric constant , has no unit. d = distance between plate

 R= resistance, Ohm , C = Capacitance , Farad e is exponent (log / ln / exp) calculator!!

Current

 = = nAve , Ampere  =  , N = no of charge , V= volume v = drift velocity , ms-1

   A = area , for wire  = 4  , d =diameter total charge Q = Ne , e = 1.6 x 10-19 C

     = == Current Density (A m  ) ,   =  -2

 E = electric field strength , NC -1 , Vm-1    =

resistivity , Ω m ,   = conductivity , Ω -1 m-1

 =  = 1 R = resistance , Ω

  ,=  , t = time collision , s . M e = mass of electron

D.C current

 =   =(+) V t   = terminal potential difference / voltage , volt , ɛ = e.m.f , volt , r = internal resistance , Ohm. R = resistance of resistor , Ohm , I = current , A

* travel is the loop u draw, look at the terminal and the direction of current to determine the sign

Potential divider

0r If Resistor change to wire .. R = L (length of wire) Wheatstone brigde

Potentiometer

 Magnetic F orce

=sin  F on carrying conductor (wire) =sin  F on moving charge ,

ɵvb = angle between v and B ɵ IB = angle between I and B q = charge, Coulomb , v = velocity of charge, ms-1 ,  B = magnetic flux density , Tesla , L = length of conductor, m

  = 2   Magnetic flux density on circular shape wire,  =  2    Magnetic flux density on solenoid,  =  = 0    Magnetic flux density on straight wire,

 µ0 = 4π x 10-7  H m-1 , I = current , l = length , N=no of turns n = N/l =Turns per unit length , r =R =radius  F on two wires,

= 2 , d = distance between 2 wires

  = Velocity of equilibrium charge in E.Field , M.Field  2 Velocity of charge between 2 plates  = √        e / m determination =  , =    2  K = kinetic energy in eV, 1 eV =1.6 x 10-19 Joule m = mass of charge / electron V = potential different, volt , B = magnetic flux density ,  E =electric field strength , r = radius

 Hall effect

 Electromagnetic

 , =  =  ∅ ∅=cos, ()

∅ (different unt) magnetic flux linkage (solenoid) = N ∅ , N= no of turns emf in linear conductor =sin  Rotating coil , ∅=cos , ɵ=ωt   Emf rotating coil,  = sin ,  =  electric flux ,Φ ≠ magnetic flux

Self inductance

 ∅= 

 L = self inductor, Henry (H) , I = current , N = no of turns

= 

 Mutual inductance

 Energy Stored in inductor U = ½ LI 2

 Alternating Current

 Z = impedance  Power in resistor

 Power in inductor ,capacitor P=0 Capacitive reactance

 f= frequency , C =capacitance , F  Inductive reactance

 L =induction , H

 Phase difference

10. a. hypothesis : zinc dipped in sodium chloride solution can  produce electric current. b. i) aim :to study two different metals dipped in electrolyte solution  produce electric current. ii. manipulated variable : The type of metal responding variable : the reading of voltmeter or production of electric current constant variable ;the volume of sodium chloride solution iii. materials and apparatus :zinc plate, copper plate, iron plate,  sodium chloride solution, beaker, voltmeter, crocodile clips , wires iv procedure : 1. Apparatus is set up as shown above. 2. result recorded and tabulated. v . tabulation :  MV (type of metal)  Zinc + copper  Iron + copper

RV the reading of voltmeter

 Page 69 Statement : Melting points of atomic subtances and molecular  subtances are different

 Hypothesis :( MV RV) Lead powder and sulphur powder have different melting point.  Aim : to study the melting point of lead powder and sulphur powder  Manipulated variable : the type of subtances (lead powder and  sulphur powder).

 Responding variable : The melting point of substance (lead powder &  sulphur powder)The reading of thermometer Constant variable: the volume of substance, The mass of substance , the amount of substance  Materials and apparatus : lead and sulphur powder, crucible, tripod  stand, thermometer, bunsen burner.  Procedure : 1. The apparatus is set as shown above/below 2. the result is recorded and tabulated Tabulation  MV the type substance  Lead powder Sulphur powder

RV melting point OC