Question

vector A is 2cm long and 60degree above x axis in first quadrant vector B is 2cm long and is 60degree below x axis in fourth quadrant. the sum A and B is a vector of magnitude. A)2cm along + y axis B)2cm along + x axis C)2cm along - x axis D)2cm along - y axis

Answer 1

Answer:

The magnitude of the resultant is 2.4

Explanation:

Given that,

\vec{A}= 2 cm

Angle \theta = 60^{\circ}

\vec{B}= 2 cm

Angle \theta = 60^{\circ}

We know that whenever two equal vectors are added and angle between them 120° then the resultant of the vector will be

The magnitude of the sum of vector A and B is

|R|=\sqrt{A^2+B^2+2ABcos\ \theta}

|R|=\sqrt{2^2+2^2+2\times2\times\ cos\ 120^{\circ}}

|R|=\sqrt{2^2+2^2+2\times2\times\dfrac{-1}{2}}

|R|=2.4

Hence, The magnitude of the resultant is 2.4