Question

The y-component of a velocity is v m/s and x-component of velocity is (root3)v m/s.The direction of the body with y-axis at this instant is
a)60 degree
b)30 degree
c)45 degree
d)0 degree​

Answer 1

Given:

The y-component of a velocity is v m/s and x-component of velocity is v√3 m/s.

To find:

instantaneous direction of the body with the y-axis.

Calculation:

Let actual resultant velocity be u .

x axis component:

$\therefore \: v \sqrt{3} = u \cos( \theta)$

y axis component:

$\therefore \: v = u \sin( \theta)$

Dividing the equations :

$\therefore \: \tan( \theta) = \sqrt{3}$

$= > \theta = 60 \degree$

So, the $\vec{u}$ is at 60° with x axis and hence is at 30° with y axis.

So, final answer is :

$\boxed{ \bold{(2) \: 30 \degree}}$

Answer 2

Explanation:

Given above the answer is 60° not 30° because it has asked angle with y axis