A small block on a frictionless, horizontal surface has a

mass of $2\mathrm{.}70{10}^{-2}kg.$ It is attached to a massless cord

passing through a hole in the surface $($Figure $1).$ The

block is originally revolving at a distance of $0\mathrm{.}300m$ from

the hole with an angular speed of $2\mathrm{.}13ra\frac{d}{s}.$ The cord

is then pulled from below, shortening the radius of the

circle in which the block revolves to $0\mathrm{.}150m.$ Model the

block as a particle.

Figure

$1$ of $1$

Part B

What is the new angular speed?

Express your answer in radians per second.

${}_2=$

$ra\frac{d}{s}$

Incorrect; Try Again; $5$ attempts remaining

Part C

Find the change in kinetic energy of the block.

Express your answer with the appropriate units.

$(\frac{?}{K}=)$