Question

The magnitude of two vectors are 3 and 4 and
their product is 6. what is the
be angle
between
them​

Answer 1

Given :

The magnitude of two vectors are 3 and 4 and their product is 6.

To Find :

Angle between them$.$

Solution :

❒ As per parallelogram law of vector addition, the magnitude of resultant R at two vectors A and B inclined to each other at angle θ is given by

• R² = A² + B² + 2AB cosθ

By substituting the given values;

➙ 6² = 3² + 4² + 2(3)(4) cosθ

➙ 36 = 9 + 16 + 24 cosθ

➙ 36 = 25 + 24 cosθ

➙ 11 = 24 cosθ

➙ cosθ = 11/24

➙ θ = cos‾¹ (11/24) ≈ 62.72°

Knowledge BoosteR :

• The latin word vector means carrier.
• The physical quantities which have no specified direction and have different values in different directions are called tensors. For example, moment of inertia.
• Null vector is a vector which has zero magnitude and an arbitrary direction.
• A negative vector of a given vector is a vector of same magnitude but acting in a direction opposite to that of the given vector.
• A vector whose initial point is fixed is called localised vector and whose initial point is not fixed is called non-localised vector.