Two particles are simultaneously projected in opposite directions horizontally from a given point in space, where gravity $g$ is uniform. If $u_1$ and $u_2$ be their initial speeds, then the time $t$ after which their velocities are mutually perpendicular is given by
$\frac{\sqrt{u_1 u_2}}{g}$
$\frac{\sqrt{u_1^2+u_2^2}}{g}$
$\frac{\sqrt{u_1\left(u_1+u_2\right)}}{g}$
$\frac{\sqrt{u_2\left(u_1+u_2\right)}}{g}$
An aeroplane flying $490 \,m$ above ground level at $100\, m/s$, releases a block. How far on ground will it strike ......... $km$
A particle is projected from a tower of height $40\ m$ in horizontal direction. Due to wind a constant acceleration is provided to the particle opposite to its initial velocity. If particle hits the ground (at the bottom of the tower) at an angle $37^o$ with horizontal, then find acceleration provided by wind to the particle
Two paper screens $A$ and $B$ are separated by distance $100 \,m$. A bullet penetrates $A$ and $B$, at points $P$ and $Q$ respectively, where $Q$ is $10 \,cm$ below $P$. If bullet is travelling horizontally at the time of hitting $A$, the velocity of bullet at $A$ is nearly .......... $m / s$
In the climax of a movie, the hero jumps from a helicopter and the villain chasing the hero also jumps at the same time from the same level. After sometime when they were at same horizontal level, the villain fires bullet horizontally towards the hero. Both were falling with constant acceleration $2\ m/s^2$ , because of parachute. Assuming the hero to be within the range of bullet, and air resistace force on bullet is negligible. Which of the following is correct
An aeroplane is flying at a constant horizontal velocity of $600\, km/hr $ at an elevation of $6\, km$ towards a point directly above the target on the earth's surface. At an appropriate time, the pilot releases a ball so that it strikes the target at the earth. The ball will appear to be falling