Aplayground merry-go-round of radius r = 2.20 m has a moment of inertia i = 275 kg · m2 and is rotating at 9.0 rev/min about a frictionless vertical axle. facing the axle, a 23.0-kg child hops onto the merry-go-round and manages to sit down on the edge. what is the new angular speed of the merry-go-round? rev/min

6.4 rpm

Explanation:

= moment of inertia of merry-go-round = 275 kgm²

m = mass of the child = 23 kg

R = radius of the merry-go-round = 2.20 m

= moment of inertia of child after jumping on merry-go-round = mR² = (23) (2.20)² = 111.32 kgm²

Total moment of inertia after child jumps is given as

= + = 275 + 111.32 = 386.32 kgm²

Total moment of inertia before child jumps is given as

= = 275 kgm²

= initial angular speed = 9 rpm

= final angular speed

using conservation of angular momentum

=

(275) (9) = (386.32)

 = 6.4 rpm

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.

hèllo, sorry i really need some more points so if you need this qustion answered than retype it