Question

SECTION 4 A small block slides down a frictionless track whose shape is described by y # x, d for x<0 and y-xldfor xo0. The value of dis M. measured in meters as usual 700 meters, and x and y are lue of d is M, 100 meters, and x and y are (a) Suppose the block starts from rest on the track, at 1 300meters What will the block's speed be when it reaches x 0? (b Suppose the block starts on the track at x -O, and is given an intial velocity of o 1O m/s to the left. The block then begins to slide up the track to the left. At what value of x will the block turn around and begin to slide down again?

Answer 1

at x = - 1.3 m y = (- 1.3)^2/2.7 t = 1.69/2.7 y = 0.626 m using v = (2gy)^1/2 = (2 times 9.8 times 0.626)^1/2 = (12.2696)^1/2 v = 3.50 m/s 1/2 times m(1.1)^2 = mgy 1/2 times (1.1)^2 = 9.8 times (x^2/2.7) 1.21/2 = 9.8 x^2/2.7 0.605 = 3.62 x^2 x^2 = 0.605/3.62 x^2 = 0.1671 x = 0.4087 m 9.8 times (0.2)^2/2.7 = 1/2 u^2 9.8 times 0.04/2.7 = 1/2 times u^2 0.392/2.7 = 0.5 times u^2 0.1451 = 0.5 times u^2 u^2 = 0.14541/0.5 u^2 = 0.2902 u = 0.538 m/s v = (gR)^1/2 m/s = (9.8)^1/2 v = 3.13 m/s According to HomeworkLib policy first four subpart solved