Question

please answer me this question...it's my request to you ...​

Answer 1

Given vectors P= 5N, Q=12N

Case 1: When resultant R = 17N; let us assume angle between vectors is A.

=

=>>R=√[ p^2+q^2+2pqcos A]=√[5^2+12^2+2*5*12*cosA]

=>289=169+120cosA.

=>120=120cosA.

=>cosA=1.

=>cosA=cos 0°

=>A=0°

Case 2: when resultant R =7N; let us assume angle between vectors is B

=>R=√[ p^2+q^2+2pqcos B]

=>7=√[5^2+12^2+2*5*12*cosB]

=>49=169+120cosB.

=> -120=120cosB

=>cosB = -1

=>cosB=cos180°

=> B=180°

Case 3: when resultant R =13N; let us assume angle between vectors is C

R=√[ p^2+q^2+2pqcos C]

=>13=√[5^2+12^2+2*5*12*cosC]

=>169=169+120cosC.

=>120cosC=0

=>cosC=0

=>cosC=cos90°

=> C=90°.

THUS:

YOUR OPTIONS NUMBER (1) WILL BE CORRECT.

I hopes its helps u.

✨✨✨✨✨✨✨

please follow me!! ✌️✌️

✨✨✨✨✨✨✨

@Abhi.

Answer 2

Option 1 is correct mate.☺