A. situation a: a 20-kg block is pressed against a relaxed spring on a frictionless surface. the spring is compressed by ∆x = 10 cm from its equilibrium position x = x 0 e . the block is released and the spring uncompresses. the speed of the block at x = x 0 e is va, f = 5.0 m/s.
b. situation b: the same 20-kg block is pressed against two relaxed springs that are attached in series on a frictionless surface. (these two springs are both identical to the spring in situation a). the entire spring assembly is compressed by ∆x = 10 cm from its equilibrium position x = x 0 e . the block is released and the spring assembly uncompresses. the speed of the block at x = x 0 e is vb, f question:
what is the value of vb, f ?
(a) 3.5 m/s
(b) 2.5 m/s/s
(c) 5.0 m/s
(d) 6.4 m/s
(e) 7.0 m/s.