Q181.The area of the triangle with vertices ˆ ˆ i j, ˆ ˆ i k and ˆ ˆ j k bis–
Correct answer: 3/2
Q182.A unit vector perpendicular to the vectors ˆ ˆ ˆ i j k and ˆ ˆ ˆ 2i 3j k + − + − is–
Correct answer: 1 ˆ ˆ ˆ 4i 3j k 26
Q183.A force ˆ ˆ ˆ 5i 3j 4k acts through the point ˆ ˆ ˆ 2i j 3k, The moment of the force about the point i 2j- k + is–
Correct answer: ˆ ˆ ˆ/8( 2i 2j k)
Q184.Unit vector perpendicular to the vectors ˆ i 2j 3k and ˆ i 2j k
Correct answer: 1 ˆ (i j k) 3
Q185.If a,b,c are non-zero vectors and (a b) c a (b c) then–
Correct answer: b is perpendicular to a and c
Q186.If ˆ ˆ a b a.b, then
Correct answer: angle between a, and b is 450
Q187.For there vectors ˆ a,b,c which of the following expression in not equal to any of the remaining there?
Correct answer: b.(a c)
Q188.If a force of magnitude 2 units act along the line joining the points ˆ i j and ˆ i k, the moment of the force above the point P(2,1,3) is–
Correct answer: i j k
Q189.The area of the triangle whose vertices are (0,0,0) (1,2,3) and (2,3,4) is–
Correct answer: 1 6 2
Q190.The area of the parallelogram having diagonals ˆ ˆ ˆ ˆ ˆ ˆ a = 3i + j- 2k and b = i - 3j+ 4k is:
Correct answer: 5 3
Q191.It is angle between two vectors a and b then a.b 0 ≥ only if:
Correct answer: 2 π ≤ θ ≤ π
Q192.If a,b,c be three non-zero vectors, then the equation a.b a.c = implies:
Correct answer: either b c = or a is orthogonal to b c
Q193.If â and b̂ are two unit vectors such that ˆ ˆ (a 2b) (5a 4b), then the angle between â and b̂ is–
Correct answer: 600
Q194.If a 1, b 5 and c 3, then a b,b c,c a
Correct answer: 0
Q195.ˆ a,b and c unit vectors such that ˆ a b c 0 then incorrect statements is–
Correct answer: ˆ ˆ/a.b b.c c.a 3
Q196.If ˆ ˆ ˆ ˆ ˆ ˆ 2 2 i + xj+ x k,i + yj+ y k and ˆ ˆ ˆ 2 i + zj+ z k are non-coplanar vectors and 2 3 x x 1+ x y y 1+ y = 0 z z 1+ z then the value of xyz is
Correct answer: –1
Q197.The triple product a + b,b+ c,c+ a is equal to:
Correct answer: 2/abc
Q198.The incorrect statement for the three vectors () () () a× b× c,b× c×a and c × a×b and is
Correct answer: they are linearly independent
Q199.If a×b – 3 a.b = 0 then the angle between a and b is
Correct answer: 3/π
Q200.ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ ˆ i ×(a×i) + j×(a× j) + k(a×k) is equal to
Correct answer: 2a