$14)$ A $10\mathrm{.}5$ kg bullet is fired into a $8\mathrm{.}5$ kg wooden block that is handing straight down,

suspended by a $1\mathrm{.}5$ m length of light line. The bullet stays in the block. The block swings

outward, so that the line it hangs from makes an angle of $7$

$0$

to the vertical.

$($a$)$ What is the velocity of the bullet before it strikes the block?

$($b$)$ What is the loss of energy in the collision?