Question

A small particle of mass m is projected at an angle θ with the X – caxis with an initial velocity v0 in the X – Y plane as shown in the figure. At a time $t=\frac{v_{0}sin\theta }{g}$ the angular momentum of the particle is


Where, $\hat{i}$ $\hat{j}$ and $\hat{k}$ are unit vectors along X, Y and Z-axis respectively.

• A.
• B. -
• C.
• D.

Answer 1

The correct option is D

$\because AngularmomentumL=rpWhere,r=v_{0}cos\theta t\hat{i}+(v_{0}sin\theta t-\frac{1}{2}g{t}^2)\hat{j}p=v_0[cos\theta \hat{i}+(v_{0}sin\theta -gt)]L=rp=-\frac{1}{2}mg{v}_0{t}^{2}cos\theta \hat{k}$