( This ( ( ( is ( the case ) ) ( if ( ( the ( electric field ) ) ( is ( ( ( lined up ) perpendicularly ) ( with ( the receptor ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ is) (NP (DT the) (NN case)) (SBAR (IN if) (S (NP (DT the) (JJ electric) (NN field)) (VP (VBZ is) (VP (VBN lined) (PRT (RP up)) (ADVP (RB perpendicularly)) (PP (IN with) (NP (DT the) (NN receptor)))))))) (. .)))
This is the case if the electric field is lined up perpendicularly with the receptor.
(ROOT (S (SBAR (IN Since) (S (NP (DT the) (JJ electric) (NN field) (NNS lines)) (VP (VBP point) (ADVP (RB radially)) (ADVP (RB away) (PP (IN from) (NP (DT the) (NN charge))))))) (, ,) (NP (PRP they)) (VP (VBP are) (ADJP (JJ perpendicular) (S (VP (TO to) (VP (VB equipotential) (NP (NNS lines))))))) (. .)))