Two particles are projected simultaneously one with velocity V up on a smooth inclined plane of inclination  300 to the horizontal and the other with a velocity 2V3  at an angle 600. The particles will be relatively at rest at the end of time is

The particles will be relatively at rest if vertical component of velocity, perpendicular to inclined plane=0 because first particle, component of velocity, perpendicular to inclined plane=0 vy=uy+ayt=0 vy=finial vertical component of velocity;uy=initial vertical component of velocity;ay=acceleration due to gravity=-gcosθ 2V3sin300−gcos300t=0 t=2v3sin300gcos300 t=2V3g×13=2V3gs