I only need part 2 done. The answer to part 1 is 11.96 A 0.4 kg bead slides on a
ID: 1449353 • Letter: I
Question
I only need part 2 done. The answer to part 1 is 11.96
A 0.4 kg bead slides on a curved wire, starting from rest at point A as shown in the figure. The segment from A to B is frictionless, and the segment from B to C is rough. The point A is at height 7.3 m and the point C is at height 0.3 m with respect to point B. Find the speed of the head at B. The acceleration due to gravity is 9.8 m/s^2. If the bead comes to rest at C, find the change in mechanical energy due to friction as it moves from B to C.Explanation / Answer
2) Its mass is M = 0.4 kg
It fell frictionlessly from rest at height H = 7.3 m, in which it gained kinetic energy E1 = MgH
It then rose from height 0 to height h = 0.3 m, during which it lost an amount of kinetic energy equal to its gain in potential energy E2 = Mgh
and the rest of its kinetic energy was lost to friction:
E = E1 - E2 = Mg(H - h)
= (0.4 kg) (9.8 m/s^2) (7.3 - 0.3) m = 27.44 J