Chapter 8: Vector Algebra I - Online Test
Q1. If the projection of 5iˆ − jˆ − 3kˆ on the vector iˆ + 3jˆ + λkˆ is same as the projection of iˆ + 3 jˆ + λkˆ on 5iˆ − jˆ − 3kˆ, then λ is equal to
Answer : Option C
Explaination / Solution:
Q2. If (1, 2, 4) and (2, - 3λ - 3) are the initial and terminal points of the vector iˆ + 5 ˆj − 7kˆ , then the value of λ is equal to
Answer : Option B
Explaination / Solution:
Q3. If the points whose position vectors 10iˆ + 3 ˆj , 12iˆ − 5 ˆj and aiˆ +11ˆj are collinear then a is equal to
Answer : Option D
Explaination / Solution:
Q4. If 
= iˆ + jˆ + kˆ, 
= 2iˆ + xjˆ +
kˆ, 
= iˆ − jˆ + 4kˆ and ⋅ ( × ) = 70 , then x is equal to
= iˆ + jˆ + kˆ, = 2iˆ + xjˆ +
kˆ, = iˆ − jˆ + 4kˆ and ⋅ ( × ) = 70 , then x is equal to
Answer : Option C
Explaination / Solution:
Q5. If = iˆ + 2 jˆ + 2kˆ ,| |= 5
and the angle between and is π/6 , then the area of the triangle formed by these two
vectors as two sides, is
= iˆ + 2 jˆ + 2kˆ ,| |= 5
and the angle between and is π/6 , then the area of the triangle formed by these two
vectors as two sides, is
Answer : Option B
Explaination / Solution:
