The resultant of two vectors#vecP# and #vecQ# is #vecR#. if the magnitude of#vecQ# is doubled , the new resultant becomes perpendicular to #vecP#. then magnitude of #vecR# is?
options are
- =
#(P+Q)#
- =
#1/2*(P+Q)#
- =Q
- P
options are
- =
#(P+Q)# - =
#1/2*(P+Q)# - =Q
- P
1 Answer
Jun 22, 2018
Option 3
Explanation:
# implies P^2 = - 2 bbQ * bbP #
-
#= P^2 + Q^2 + 2 bbP*bbQ# -
#= - 2 bbQ * bbP + Q^2 + 2 bbP*bbQ = Q^2#