A particle has been projected with a speed of 20 ms^-1 at an angle of 30^o with the horizontal The time taken when the velocity vector becomes perpendicular to the initial velocity vector is

see full answer

High-Paying Jobs That Even AI Can’t Replace — Through JEE/NEET

🎯 Hear from the experts why preparing for JEE/NEET today sets you up for future-proof, high-income careers tomorrow.

An Intiative by Sri Chaitanya

4 s

3 s

Not possible in this case

2 s

answer is D.

(Unlock A.I Detailed Solution for FREE)

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

$\begin{array}{l} \vec{u} = 20 \cos 30 \hat{i} + 20 \sin 30 \hat{j} \\ Now, \vec{v} = 20 \cos 30 \hat{i} + (20 \sin 30 - gt) \hat{j} \end{array}$

Let $\vec{v}$ be perpendicular to $\vec{u}$ at time t, then

$\vec{v} \cdot \vec{u} = 0 \Rightarrow t = 4 s$

Here time of flight, T = 2 s. So it is not possible at any instant.

Watch 3-min video & get full concept clarity

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test