Velocity of a particle moving in a curvilinear path in a horizontal $X$ $Y$ plane varies with time as $\vec v = (2t\hat i + t^2 \hat j) \ \ m/s.$ Here, $t$ is in second. At $t = 1\ s$
acceleration of particle is $8\ m/s^2$
tangential acceleration of particle is $\frac{4}{{\sqrt 5 }} \ m/s^2$
radial acceleration of particle is $\frac{6}{{\sqrt 5 }} \ m/s^2$
radius of curvature to the path is $\frac{5\sqrt 5}{{2 }} \ m$
The coordinates of a particle moving in a plane are given by $x = a\cos (pt)$ and $y(t) = b\sin (pt)$ where $a,\,\,b\,( < a)$ and $p$ are positive constants of appropriate dimensions. Then
The initial velocity of a projectile is $\vec u = (4\hat i + 3\hat j)\,m/s$ it is moving with uniform acceleration $\vec a = (0.4\hat i + 0.3\hat j)\, m/s^2$ The magnitude of its velocity after $10\,s$ is.........$m/s$
A river is flowing due east with a speed $3\, ms^{-1}$. A swimmer can swim in still water at a speed of $4\, ms^{-1}$ (figure).
$(a)$ If swimmer starts swimming due north, what will be his resultant velocity (magnitude and direction) ?
$(b)$ If he wants to start from point A on south bank and reach opposite point $B$ on north bank,
$(i)$ Which direction should he swim ?
$(ii)$ What will be his resultant speed ?
$(c)$ From two different cases as mentioned in $(a)$ and $(b)$ above, in which case will he reach opposite bank in shorter time ?