Let \(→{b}=^i+^j+λ k\) , λ ∈ R. If vector a is a vector such that → a×→ b= 13^i −^j−4^k and→ a.→ b+ 21 =0, then (→ b − → a) . ( → k − ^ j ) + ( → b + → a ) . ( ^ i − ^ k ) is equal to
Correct Answer: 14
Solution and Explanation
The correct answer is: 14.
Top Questions on Vectors
- Number of functions \( f: \{1, 2, \dots, 100\} \to \{0, 1\} \), that assign 1 to exactly one of the positive integers less than or equal to 98, is equal to:
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- For a force F to be conservative, the relations to be satisfied are:
A. \(\frac{\partial F_y}{\partial x} - \frac{\partial F_x}{\partial y} = 0\)
B. \(\frac{\partial F_z}{\partial y} - \frac{\partial F_y}{\partial z} = 0\)
C. \(\frac{\partial F_x}{\partial z} - \frac{\partial F_z}{\partial x} = 0\)
D. \(\frac{\partial F_y}{\partial x} - \frac{\partial F_x}{\partial y} = \frac{\partial F_z}{\partial y} - \frac{\partial F_y}{\partial z} = \frac{\partial F_x}{\partial z} - \frac{\partial F_z}{\partial x} \neq 0\)
Choose the correct answer from the options given below: - If \(|\vec{A}+\vec{B}| = |\vec{A}-\vec{B}|\) then the angle between vectors \(\vec{A}\) and \(\vec{B}\) is:
Questions Asked in JEE Main exam
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Concepts Used:
Vector Basics
What is a Vector Quantity?
Vector Quantity is a physical quantity that is specified not only by its magnitude but also by its direction. A vector quantity whose magnitude is equal to one and has direction is called a unit vector.
Examples of vector quantity are-
- Displacement
- Linear momentum
- Momentum
- Acceleration
- Force
- Electric field
- Angular velocity
- Polarization