Kinematics Question 432
Question: The resultant of $ \vec{A} $ and $ \vec{B} $ it’s $ {{\vec{R}}_1} $ . On reversing the vector $ \vec{B}, $ the resultant becomes $ {{\vec{R}}_2} $ . What is the value of $ R_1^{2}+R_2^{2}? $
Options:
A) $ A^{2}+B^{2} $
B) $ A^{2}-B^{2} $
C) $ 2(A^{2}+B^{2}) $
D) $ 2(A^{2}-B^{2}) $
Correct Answer: C [c] $ R_1^{2}=A^{2}+B^{2}+2AB\cos \theta $ $ R_2^{2}=A^{2}+B^{2}-2AB\cos \theta $Show Answer
Answer:
Solution:
$ \therefore $ $ R_1^{2}+R_2^{2}=2(A^{2}+B^{2}) $