Electric Forces and Electric field
Mass of proton=1.673×10-27kg
Mass of neutron =1.675×10-27kg





















Proton(+), Electron(-) and Neutron (no electric charge)--neutral
Proton(+e) and electron(-e)
q=Ne **e=1.60×10-19C
Gains of electron acquires an excess of (-) charge, Loss of electrons acquires a (+) charge
(+) and (+) - - - - repulsion - - - - (-) and (-) *(like charges repel)
(+) and (-) - - - - attraction *(unlike charges attract each other)
LAW OF CONSERVATION OF ELECTRIC CHARGE* During any process, the net electric charge of
an isolated system remains constant
N. B electric force also called electrostatic force
Electric conductor *substances that readily conduct electric charge(ELECTRONS MOVE FREELY)
E.g copper,Al,Ag and gold are used in electric wiring
Electric insulator * materials Tha conduct electric charge poorly (ELECTRONS CANNOT MOVE
FREELY).( E. g rubber, plastics and wood*prevent electric charge from going where it is not
wanted)
CHANGING BY CONDUCTION* Charging a neutral object by touching it with a charged object
*Transfer electrons
* neutral object get the same charge as charged object
CHANGING BY INDUCTION *Charged object never touches the neutral object
* A separation of charge can be used to give an object a net charge
CHANGING BY INDUCTION AND GROUNDING *Charging a neutral object by induction then
grounding *Transfer electrons
COULOMB’s LAW states that the magnitude F of electrostatic force exerted by one point
charge q1 on another charge q2 is directly proportional to the magnitud |q1| and|q2| of
charges and inversely proportional to the square of distance r between them.
Net force=F 12 +F 13
N. B. F 2 =F x 2 + F y 2
*Fx= Fcos 0 , Fy= Fsin0 and tanO=Fy/Fx
ELECTRIC FIELD is a vector *SI units :(N/C).
E=F/q
(+) electric field lines (outward) and (-) electric lines (inwards)
THANK YOU!!!! WORK HARD LIKE A DONKEY, DON’T GIVE UP….. KEEP GOING AND LET YOUR
DREAM COME TRUE… DON’T COMPARE YOURSELF WITH OTHER PEOPLE.