SUPERPOSITION PRINCIPLE OF CHARGES SUPERPOSITION PRINCIPLE OF CHARGES RESULTANT VECTOR - the sum oftwo or more vect ors combin ed - a singl e vector whic h that has the same effect as all the vectors combined - can be det ermined eit her graphi cally or analytically RESULT ANT VECTOR - the sum of twoor more vecto rs combined - a singl e vector whic h that has the same effect as all the vectors combined - can be determined eit her graphi cally or analytically +q 1 +q 2 TWO LIKE CHARGES OF EQUALMAGNITUDES F q1 F q2 The two charges repel each other with an equal magnitude of force but in opposite direction. +q 1 +q 2 TWO LIKE CHARGES OF EQUALMAGNITUDES F q1 F q2 The two charges repel each other with an equal magnitude of force but in opposite direction. +q 1 -q 2 TWO UNLIKE CHARGES OF EQUALMAGNITUDES F q2 F q1 Th e two ch ar ge s attract ea ch other wi th an eq ua l ma gn it ud e of fo rce bu t in opp osite dire ction. +q 1 -q 2 TWO UNLIKE CHARGES OF EQUALMAGNITUDES F q2 F q1 The two char ge s att ra ct ea ch ot he r with an equa l ma gn it ud e of fo rc e bu t in opp osit e dire ctio n. THREE IDENTICAL POINT CHARGES ALONG A STRAIGHT LINE +q1 +q2 +q3 F q3 F q2 F q3 F q1 F q2 F q1 A mo ng th e t hr ee p oi nt ch arge s onl y +q 2 ex peri ence zero net force. The other two point charges, +q 1 and +q 3 , exper ience greater net force but they act in opposite direction. THREE IDENTICAL POINT CHARGES ALONG A STRAIGHT LINE +q 1 +q 2 +q 3 F q3 F q2 F q3 F q1 F q2 F q1 Among th e three po int char ges only +q 2 expe rienc e zero net forc e. The other two poin t charges, +q 1 and +q 3 , experience greater net force but they act in opposite direction. If the magnit ude of the identical poi nt cha rges is 1µC and the distance between q 1 and q 2 is the same as between q 2 and q 3 , which is 1mm, find the net force on each point charge. ) ( 3 2 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 2 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x NNNFnet11250 ) 2250 ( 9000 F net on q 1 If the magnit ude of the identi cal point charges is 1µC and the distance between q 1 and q 2 is the same as between q 2 and q 3 , whic h is 1mm, find the net force on each point charge. ) ( 3 2 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 2 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x NNNFnet11250 ) 2250 ( 9000 F net on q 1 F net on q 2 ) ( 3 1 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x 0 ) 9000 ( 9000 NNFnetF net on q 3 1 2 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 2 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x NNNFnet11250 2250 9000 F net on q 2 ) ( 3 1 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x 0 ) 9000 ( 9000 NNFnetF net on q 3 1 2 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 2 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x NNNFnet11250 2250 9000 +q 1 +q 2 TWO LIKE CHARGES OF EQUALMAGNITUDES F q1 F q2 The two charges repel each other with an equal magnitude of force but in opposite direction. +q 1 +q 2 TWO LIKE CHARGES OF EQUALMAGNITUDES F q1 F q2 The two charges repel each other with an equal magnitude of force but in opposite direction. If the magnitude of the three point charges is 1µC and the distance between q 1 and q 2 is the same as between q 2 and q 3 , which is 1mm, find the net force on each point charge. ) ( 3 2 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 2 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x NNNFnet6750 ) 2250 ( 9000 F net on q 1 If the magnitude of the three point charges is 1µC and the distance between q 1 and q 2 is the same as between q 2 and q 3 , which is 1mm, find the net force on each point charge. ) ( 3 2 q q netFFF2 3 6 6 2 2 9 2 3 6 6 2 2 9 ) 10 2 ( ) 10 1 )( 10 1 )( /10 9 ( ) 10 1 ( ) 10 1 )( 10 1 )( /10 9 ( m x Cx Cx CNm x m x Cx Cx CNm x NNNFnet6750 ) 2250 ( 9000 F net on q 1
