Question

IX CLASS - PHYSICS
3.
Vector A is 2cm long and is 60° above the x-axis in the first quadrant, vector B is zem
long and is 60° below the x-axis in the fourth quadrant. Find A+ B.​

Answer 1

Answer:

\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

Explanation: