Two particles \(A\) and \(B\), move with constant velocities \(\overrightarrow{v_1}\) and \(\overrightarrow{v_2}\). At the initial moment their position vector are \(\overrightarrow {r_1}\) and \(\overrightarrow {r_2}\) respectively. The condition for particles \(A\) and \(B\) for their collision to happen will be:
1. \(\overrightarrow{r_{1  }} . \overrightarrow{v_{1}}   = \overrightarrow{r_{2  }} . \overrightarrow{v_{2}}\)
2. \(\overrightarrow{r_{1}} \times\overrightarrow{v_{1}}   = \overrightarrow{r_{2}} \times \overrightarrow {v_{2}}\)
3. \(\overrightarrow{r_{1}}-\overrightarrow{r_{2}}=\overrightarrow{v_{1}} - \overrightarrow{v_{2}}\)
4. \(\frac{\overrightarrow{r_{1}} - \overrightarrow{r_{2}}}{\left|\overrightarrow{r_{1}} -  \overrightarrow{r_{2}}\right|} =   \frac{\overrightarrow{v_{2}} -  \overrightarrow{v_{1}}}{\left|\overrightarrow{v_{2}} -   \overrightarrow{v_{1}}\right|}\)$\frac{\left|\stackrel{}{}\right|}{}$

A particle starting from the point \((1,2)\) moves in a straight line in the XY-plane. Its coordinates at a later time are \((2,3).\) The path of the particle makes with \(x\)-axis an angle of:

A particle moves along a parabolic path \(y =9x^2\) in such a way that the \(x\) component of the velocity remains constant and has a value of \(\frac{1}{3}~\text{m/s}\)${\mathrm{}}^{}$. It can be deduced that the acceleration of the particle will be:
1. \(\frac{1}{3}\hat j~\text{m/s}^2\)
2. \(3\hat j~\text{m/s}^2\)
3. \(\frac{2}{3}\hat j~\text{m/s}^2\)
4. \(2\hat j~\text{m/s}^2\)

Three balls are thrown from the top of a building with equal speeds at different angles. When the balls strike the ground, their speeds are \(v_{1} , v_{2}\) \(\text{and}\) \(v_{3}\) respectively, then:
           

1. \(v_{1} > v_{2} > v_{3}\)
2. \(v_{3} > v_{2} = v_{1}\)
3. \(v_{1} = v_{2} = v_{3}\)
4. \(v_{1} < v_{2} < v_{3}\)${\mathrm{}}_{}$

Figure below shows a body of mass \(M\) moving with a uniform speed \(v\) on a circular path of radius, \(R\). What is the change in acceleration in going from \(P_1\) to \(P_2\)? 
              

1. zero
2. \(v^{2} / 2 R\)
3. \(2 v^{2} / R\)
4. \(\frac{v^{2}}{R} \times \sqrt{2}\)

A particle is projected with a speed \(u\) at an angle \(\theta\) to the horizontal. Radius of curvature at highest point of its trajectory is?
1. \(\frac{u^{2} \cos^{2} \theta}{2 g}\)
2. \(\frac{\sqrt{3} u^{2}\cos^{2} \theta}{2 g}\)
3. \(\frac{u^{2} \cos^{2} \theta}{g}\)
4. \(\frac{\sqrt{3} u^{2} \cos^{2} \theta}{g}\)

Two particles \(A\) and \(B\) are moving in a uniform circular motion in concentric circles of radii \(r_A\) and \(r_B\) with speeds \(v_A\) and \(v_B\) respectively. Their time periods of rotation are the same. The ratio of the angular speed of \(A\)  to that of \(B\) will be:

A particle is projected from a horizontal plane (\(x\text-z\) plane) such that its velocity vector at time \(t\) is given by \(\overrightarrow{v}=a \hat{i}+(b-c t )\hat{j}.\) Its range on this horizontal plane is given by: 

A car turns at a constant speed on a circular track of radius \(100\) m, taking \(62.8\) s for every circular lap. The average velocity and average speed for each circular lap, respectively, is:

For a projectile projected at angles \((45^{\circ}-\theta)\) and \((45^{\circ}+\theta)\), the horizontal ranges described by the projectile are in the ratio of:
1. \(1:1\)
2. \(2:3\)
3. \(1:2\)
4. \(2:1\)