A stone tied to the end of a string \(80\) cm long is whirled in a horizontal circle at a constant speed. If the stone makes \(14\) revolutions in \(25\) s, what is the magnitude of the acceleration of the stone?

1.	\(8.1\) ms–2	2.	\(7.7\) ms–2
3.	\(8.7\) ms–2	4.	\(9.9\) ms–2

A particle starts from the origin at \(t=0\) sec with a velocity of \(10\hat j~\text{m/s}\) and moves in the \(x\text-y\) plane with a constant acceleration of \((8.0\hat i +2.0 \hat j)~\text{m/s}^2\). At what time is the \(x\text-\)coordinate of the particle \(16~\text{m}\)?
1.  \(2\) s
2.  \(3\) s
3.  \(4\) s
4.  \(1\) s

A particle is moving along a circle such that it completes one revolution in \(40\) seconds. In \(2\) minutes \(20\) seconds, the ratio of \(|displacement| \over distance\) will be:
1. \(0\)
2. \(\dfrac{1}{7}\)
3. \(\dfrac{2}{7}\)
4. \(\dfrac{1}{11}\)

Consider the motion of the tip of the second hand of a clock. In one minute (assuming \(R\) to be the length of the second hand), its:

A person reaches a point directly opposite on the other bank of a flowing river while swimming at a speed of \(5~\text{m/s}\)at an angle of \(120^\circ\) with the flow. The speed of the flow must be:
1. \(2.5~\text{m/s}\)
2. \(3~\text{m/s}\)
3. \(4~\text{m/s}\)
4. \(1.5~\text{m/s}\)

A car with a vertical windshield moves in a rain storm at a speed of \(40\) km/hr. The rain drops fall vertically with a constant speed of \(20\) m/s. The angle at which raindrops strike the windshield is:
1. \(\tan^{- 1} \frac{5}{9}\)
2. \(\tan^{- 1} \frac{9}{5}\)
3. \(\tan^{- 1} \frac{3}{2}\)
4. \(\tan^{- 1} \frac{2}{3}\)

A particle is projected from the origin and moves in the \(xy\text-\)plane with velocity:
        \(\vec{v} = 3 \hat{i} + 6 x \hat{j},\)
where \(\hat i\) and \(\hat j\)​ are unit vectors along the \(x\) and \(y\text-\)axes, respectively. Which of the following represents the equation of the trajectory of the particle?

The position coordinates of a projectile projected from ground on a certain planet (with no atmosphere) are given by
\(y =4 t - 2 t^{2}~ \text{m}\)  and \(x =3t\) metre, where \(t\) is in seconds and point of projection is taken as the origin. The angle of projection of projectile with vertical is:
1. \(30^{\circ}\)
2. \(37^{\circ}\)
3. \(45^{\circ}\)
4. \(60^{\circ}\)

The velocity at the maximum height of a projectile is \(\frac{\sqrt{3}}{2}\) times its initial velocity of projection \((u)\). Its range on the horizontal plane is:
1. \(\frac{\sqrt{3} u^{2}}{2 g}\)
2. \(\frac{3 u^{2}}{2 g}\)
3. \(\frac{3 u^{2}}{ g}\)
4. \(\frac{u^{2}}{2 g}\)

The equation of a projectile is \(y = ax -bx^{2}\). Its horizontal range is?
1. \(\frac{a}{b}\)
2. \(\frac{b}{a}\)
3. \(a+b\)
4. \(b-a\)