Question

Two vectors have magnitudes 3 unit and 4 unit respectively . What should be the angle between them if the magnitude of the resultant is

(a) 1 unit
(b) 5 unit and
(c) 7 unit

Concept of Physics - 1 , HC VERMA , Chapter - "Physics and Mathematics"

Answer 1

Hope it will help u... Plz mark it as brainliest... :)

Answer 2

Thanks for asking the question!

SOLUTION::

Magnitude of vector a , |a| = 3 m
Magnitude of vector b , |b| = 4 m

(a) If resultant , R = 1 unit then,
     R = √(a²+b²+a.b.cos Ф) 
     1 = √(3² + 4² + cos Ф)
     Ф = 180°

(b) If resultant , R = 5 unit then,
     R = √(a²+b²+a.b.cos Ф) 
     5 = √(3² + 4² + cos Ф)
     Ф = 90°

(c) If resultant , R = 7 unit then,
     R = √(a²+b²+a.b.cos Ф) 
     7 = √(3² + 4² + cos Ф)
     Ф = 0°

Hope it helps!