## Question:

A 323 gr bullet (1 lb = 7000 gr) hits a 2 kg block that is initially at rest. After the collision, the bullet becomes embedded in the block, and they slide a distance of 0.31 m. If the coefficient of friction between the block and the ground is ${ \mu }_{ k }$ = 0.7, determine the preimpact speed of the bullet. Although the definition of the unit “grain” is given in terms of pounds, express the answer in SI units.