To be able to describe the motion of rigid bodies by applying the conservation of linear and angular momenta.
If the sum of all the linear impulses acting on a system of connected rigid bodies is zero, the linear momentum of the system is conserved. Mathematically, this relationship is expressed as
(∑syst. linearmomentum)1=(∑syst. linearmomentum)2(∑momentumsyst. linear)1=(∑momentumsyst. linear)2
and is called the conservation of linear momentum. If the sum of all the angular impulses (created by the external forces that act on the system) is negligible or zero, then the angular momentum of a system of connected rigid bodies is conserved about the system's center of mass or about a fixed point. Mathematically, this relationship is expressed as
(∑syst. angularmomentum)1=(∑syst. angularmomentum)2(∑momentumsyst. angular)1=(∑momentumsyst. angular)2
and is called the conservation of angular momentum. Which of the following scenarios demonstrate the conservation of either linear or angular momentum?
Check all that apply.
A parent pushes a merry-go-round and, consequently, it spins faster.From opposite sides of a room, two identical balls of putty move toward each other, without friction, at the same velocity and, eventually, they collide; the result is one ball of putty with zero velocity.A penny is dropped from the top of a building and its velocity increases as it falls due to the acceleration from gravity.An ice skater tucks in her arms during a spin and her angular velocity increases.