A frictionless surface gradually changes direction from horizontal to vertical.
ID: 2032753 • Letter: A
Question
A frictionless surface gradually changes direction from horizontal to vertical. A wooden block of mass M 250 g is initially at rest on the horizontal part of the surface. A bullet with mass m 12 g and speed vo -305 m/s is traveling horizontally toward the center of the block. The bullet becomes imbedded in the block during the collision and the combined mass travels around the frictionless curve. (Figure 1) What maximum change in height does the center of mass of the bullet-block system undergo? Ignore air resistance and assume g 9.8 m/s2. Submit Request Answer Part B igure 1 of 1 Find the energy lost in the collision. E lost-Explanation / Answer
A)
let v is the speed of the block just after the bullet embeded into it.
Apply conservation of moemtnum
(m + M)*v = m*vo
==> v = m*vo/(m + M)
= 0.012*305/(0.012 + 0.25)
= 13.97 m/s
maximum height reached, h = v^2/(2*g)
= 13.97^2/(2*9.8)
= 9.96 m <<<<<<-----Answer
B) E_lost = (1/2)*m*vo^2 - (1/2)*(m + M)*v^2
= (1/2)*0.012*305^2 - (1/2)*(0.012 + 0.25)*13.97^2
= 533 J <<<<<<-----Answer