Work Energy and...

A ball with velocity $$9\ m/s$$ collides with another similar stationary ball. After the collision the two balls move in directions making an angle of  $$30^o$$ with the initial direction. The ratio of the speeds of balls after the collision will be :

A bullet weighing 10 g and moving at 300 ms$$^{-1}$$ strikes a 5 kg block of ice and drops dead. The ice block is sitting on frictionless level surface. The speed of the block, after the collision is :

A toy car is tied to the end of an unstretched string of a length, $$a$$. When revolved, the toy car moves in a horizontal circle of radius $$2a$$ with time period, $$T$$. If it is now revolved in a horizontal circle of radius $$3a$$ with a period $$T'$$ with the same force, then

In the elastic collision of heavy vehicle moving with a velocity 10 ms$$^{-1}$$ and a small stone at rest, the stone will fly away with a velocity equal to : 

A sphere of mass m, moving with a speed v, strikes a wall elastically at an angle of incidence $$\theta$$. If the speed of the sphere before and after collision is the same and the angle of incidence and velocity normally towards the wall the angle of rebound is equal to the angle of incidence and velocity normally towards the wall is taken as negative then, the change in the momentum parallel to wall is :

A body of mass $$1\ kg$$ is rotating in a vertical circle of radius $$1\ m$$. What will be the difference in its kinetic energy at the top and bottom of the circle? 

A ball of mass $$m$$ moving with velocity $$v$$ collides elastically with wall and rebounds. The change in momentum of the ball will be :

What will be the potential energy of a body of mass 5 kg kept at a height of 10 m ?

The velocity of a particle at highest point of the vertical circle is $$\sqrt{3rg}$$. The tension at the lowest point, if mass of the particle is $$m$$, is

Two objects that are moving along an xy-plane on a frictionless floor collide. Assume that they form a closed, isolated system. The following table gives some of the momentum components (in kilogram meters per second) before and after the collision. What are the mission values (a, b):