AP EAMCET202023 Sep 2020Morning ShiftMathematicsVector AlgebraActual
If P Q R S T is a pentagon, then the resultant of forces P Q ¯ , P T ¯ , Q R ¯ , S R ¯ , T S ¯ and P S ¯ is
Options
- A3 PT ¯
- B3 PQ ¯
- C3 PS ¯
- D0 ¯
Correct answer
C. 3 PS ¯
Step-by-step solution
Given, PQRST is a pentagon Let, p - , q - , r - , s -   a n d   t - be the position vectors associated with P - ,   Q ,   - R - ,   S   - a n d   T - respectively Now, P Q - + P T - + Q R - + S R - + T S - + P S - = ⇒ ( q - - p - ) + ( t - - p - ) + ( r - - q - ) + ( s - - r - ) + ( s - - t ) + ( s - - p - ) ⇒ 3 s - - 3 p - ⇒ 3 ( s - - p - ) ⇒ 3 P S - .