Two particles start simultaneously from the same point and move along two straight lines, one with uniform velocity $v$ and other with a uniform acceleration $a.$ If $\alpha$ is the angle between the lines of motion of two particles then the least value of relative velocity will be at time given by
$(v/a)\,\, sin \,\,\alpha$
$(v/a)\,\, cos \,\,\alpha$
$(v/a)\,\, tan \,\,\alpha$
$(v/a)\,\,cot \,\,\alpha$
A particle starts moving rectilinearly at time $t = 0$ such that its velocity $'v'$ changes with time $'t'$ according to the equation $v = t^2 - t$ where $t$ is in seconds and $v$ is in $m/s.$ The time interval for which the particle retards is
Let $\vec v$ and $\vec a$ denote the velocity and acceleration respectively of a body in one-dimensional motion
A particle starts from the origin at $\mathrm{t}=0$ with an initial velocity of $3.0 \hat{\mathrm{i}} \;\mathrm{m} / \mathrm{s}$ and moves in the $x-y$ plane with a constant acceleration $(6.0 \hat{\mathrm{i}}+4.0 \hat{\mathrm{j}}) \;\mathrm{m} / \mathrm{s}^{2} .$ The $\mathrm{x}$ -coordinate of the particle at the instant when its $y-$coordinate is $32\;\mathrm{m}$ is $D$ meters. The value of $D$ is
The position vector of an object at any time $t$ is given by $3 t^2 \hat{i}+6 t \hat{j}+\hat{k}$. Its velocity along $y$-axis has the magnitude