
Let two forces be P and Q. Given P+Q=18 and Pa^+Qb^=12c^⇒Pa^−12c^=Qˉb^ ⇒P2+144=Q2=(18−P)2;⇒P2+144=324−36P+P2⇒36P=180⇒P=5 and Q=13 (where a and b are unit vectors along P and Q ).
JEE Main 2002 — Mathematics Vectors & 3D Geometry
The sum of two forces is 18 N and resultant whose direction is at right angles to the smaller force is 12 N. The magnitude of the two forces are
Held on 30 Apr 2002 · Verified 6 Jul 2026.
13, 5
12, 6
14, 4
11, 7
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