A kid's merry-go-round in a park is a thin 150 kg disk (I = ½ MR?) with a radius of 3 m mounted to rotate freely about a central axis. On the edge of %3D the disk is an essentially massless bar. A 25 kg child jumps onto the bar (tangentially to the outer rim of the disk) at a speed of 12 m/s and a distance of 3 m from the rotation axis. If we think of the child as being essentially a point mass, what is the angular velocity of the system after the collision?
Rigid Body
A rigid body is an object which does not change its shape or undergo any significant deformation due to an external force or movement. Mathematically speaking, the distance between any two points inside the body doesn't change in any situation.
Rigid Body Dynamics
Rigid bodies are defined as inelastic shapes with negligible deformation, giving them an unchanging center of mass. It is also generally assumed that the mass of a rigid body is uniformly distributed. This property of rigid bodies comes in handy when we deal with concepts like momentum, angular momentum, force and torque. The study of these properties – viz., force, torque, momentum, and angular momentum – of a rigid body, is collectively known as rigid body dynamics (RBD).
Step by step
Solved in 2 steps with 2 images