Amerry-go-round is a common piece of playground equipment. a 3.0-m-diameter merry-go-round, which can be modeled as a disk with a mass of 230 kg , is spinning at 17 rpm. john runs tangent to the merry-go-round at 4.2 m/s. what is the merry-go-round's angular velocity, in rpm, after john jumps on?

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e