Q01.If the vectors a, b and c form the sides BC, CA and AB respectively of a ∆ ∆ ∆ABC, then:
Correct answer: a×b = b×c = c×a
Q02.Let ˆ ˆ ˆ a = 3i + 2j+ 2k and ˆ ˆ ˆ b = i + 2j- 2k be two vectors. If a vector perpendicular to both the vectors a + b and a - b has the magnitude 12, then one such vector is:
Correct answer: () ˆ ˆ ˆ 4 2i - 2j- k
Q03.If a unit vector â makes angles π 3 with î, π 4 with ĵ and () θ 0, π ∈ with k̂, then value of θ is:
Correct answer: 2 3 π
EnglishBihar (TRE 2.0)-2023
Q04.The value of () () a -b × a + b is
Correct answer: 2 ( )/a×b
EnglishBihar (TRE 2.0)-2023
Q05.Time period is a
Correct answer: scalar quantity
Q06.If a,b,c are unit vectors, then 2 2 2 ˆ ˆ ˆ ˆ ˆ ˆ a b b c c a − + − + − does not exceed:
Correct answer: 9
Q07.If a and b are unit vector, then correct statement is-
Correct answer: a + b is unit vector, if angle between a and b is 2 3 π
Q08.If a, b and c are unit vectors such that a + b + c = 0, then the value of a. b + b. c + c.a is:
Correct answer: - 3 2
Q09.The value of () i j k j k i k i j × + + × + + × + is equal to:
Correct answer: 0
Q10.For any vector a, the value of () () () 2 2 2 ˆ ˆ a i a j a k × + × + × is:
Correct answer: 2/2a
Q11.If () () () ˆ ˆ ˆ ˆ ˆ ˆ i i a j j a k k a m.a, × × + × × + × × = then m is equal to:
Correct answer: –2
Q12.If a b c + = and a b c, + = then angle between a and b is:
Correct answer: 0°
Q13.If | a | 4 | b | 5 and a. b 10 = then the value | a b | × is:
Correct answer: 10 3
Q14.Vectors a i 2j 3k, b 2i 3j k, = − + = − + and c 3i j 2k, = − − are given. The value of a b c is:
Correct answer: 14
Q15.Let a = (2 î – ĵ + k̂), b = (î + 2 ĵ – k̂) and c = (î + ĵ–2 k̂) be three vector. A vector in the plane of b and c whose projection on a is zero, will be
Correct answer: ĵ + k̂
Q16.A,BandC are unit vectors. A is perpendicular to both B and C and angle between B and C is 30º. Then vector A is -
Correct answer: 2(B C)/± ×
Q17.a;b;c are unit vectors b and c are non collinear vector. If a × (2b ×c) =b, then angle between a and b is -
Correct answer: 90º
Q18.The midpoints of sides AB and AC of a triangle ABC are points D and E, respectively, then resultant of forces represented by BE and DC in magnitude and direction is represented by -
Correct answer: 3 BC 2
Q19.If additive inverse vector of vector of vector pi + 2j – 3k is the vector (ab i + b j + pk), then which of the following is true (a>0)?
Correct answer: p = 9, b = 4, a = 81/4
Q20.Let − x = 2i + j 2k and y = i + j.If z is a vector such that x.z = z, z x = 2 2 − − and the angle between x×y and z is 30° ° °, then the magnitude of the vector ()× x×y z is _________
Correct answer: 3/2