Question 1 :
A body of mass, $m$, is rotated in a vertical circle of&#160;radius, $R$, by means of a light string. If the velocity&#160;of body is $\sqrt{5gR}$ at the lowest point of vertical&#160;circle, then tension in the string is:<br/>

Question 2 :
Calculate the work done in lifting &#160;water of 200 kg through a vertical distance of 6 m. $\left ( g=10&#160; m&#160; s^{-2} \right )$<br/>

Question 3 :
Two bodies of equal masses are placed at heights $h$ and $2h$. Find the ratio of their gravitational potential energies.

Question 4 :
Find the vertical height through which a body of mass $0.5kg$ is lifted if the energy spent in doing so is $1.0J$. Consider $g=10ms^{-2}$.

Question 5 :
&#160;A bullet of mass 20 gm is fired from a rifle of mass 20 kg with a muzzle velocity of $200\ ms^{-1}$. Find the velocity of recoil of the rifle.<br/>

Question 6 :
A man of 30 kg jumps up to a height of 2 m . What is his potential energy at the highest point ?

Question 7 :
A bus is moving with a speed of 10$ms^{-1}$ on a straight road. A scooterist wishes to overtake the bus in 100s. If the bus is at a distance of 1 km from the scooterist, with what speed should the scooterist chase the bus?

Question 8 :
A body of weight 1 newton has a potential energy of 1 joule relative to the ground when it is at a height of:

Question 9 :
What is the angle between two vector forces of equal magnitude such that their resultant is one-third of either of the original forces?

Question 10 :
Concrete mixture is made by mixing cement, stone and sand in a rotating cylindrical drum. If the drum rotates too fast, the ingredients remain stuck to the wall of the drum and proper mixing of ingredients does not take place. The maximum rotational speed of the drum in revolutions per minute(rpm) to ensure proper mixing is close to : (Take the radius of the drum to be $1.25$ in and its axle to be horizontal)

Question 11 :
What is the centripetal acceleration of the ball if its mass is doubled?

Question 12 :
If the speed of body moving in circle is doubled and the radius is halved,&#160;its centripetal acceleration becomes<p></p>

Question 13 :
A particle is revolving in a circle with increasing its speed uniformly. Which of the following is constant?<br>

Question 15 :
In order to keep a body moving in a circle, there exists a force on it that is directed toward center of circle. This force is known as

Question 17 :
In uniform circular motion, the velocity vector and acceleration vector are:

Question 18 :
The average acceleration vector for a particle having a uniform circular motion in one complete revolution.

Question 19 :
A car moving along a circular path of radius $R$ with uniform speed covers an angle $\theta$&#160;during&#160;a given&#160;time $t$.&#160;What is&#160;its&#160;average velocity?

Question 20 :
A particle is projected from ground with some initial velocity making an angle $45^o$ with the horizontal. It reaches at height of 7.5 m above the ground while it travels a horizontal distance of 10 cm from the point of projection. The initial speed of the projection is&#160;