Find the time after which the particle's initial velocity will be perpendicular to instantaneous velocity when it is projected with 30 m/s from horizontal ground by making an angle 60° with vertical.

Question

Find the time after which the particle's initial velocity will be perpendicular to instantaneous velocity when it is projected with 30 m/s from horizontal ground by making an angle 60° with vertical. (A) 6second (B) 2√3second (C) 3second (D) Never possible

Tardigrade Admin · Accepted Answer

Angle made by projectile with horizontal is 30° which is less than 45° . Hence the two velocities are not perpendicular at any instant

Q. Find the time after which the particle's initial velocity will be perpendicular to instantaneous velocity when it is projected with $30 m / s$ from horizontal ground by making an angle $6 0^{\circ}$ with vertical.

$6 seco n d$

$23 seco n d$

$3 seco n d$

Never possible

Angle made by projectile with horizontal is $3 0^{\circ}$ which is less than $4 5^{\circ} .$ Hence the two velocities are not perpendicular at any instant

Q. Find the time after which the particle's initial velocity will be perpendicular to instantaneous velocity when it is projected with 30m/s from horizontal ground by making an angle 60∘ with vertical.

6second

23​second

3second