Two frictionless mass–spring systems are set into motion on identical horizontal surfaces. System A has spring constant k and amplitude 2A. System B has spring constant 4k and amplitude A. When each block passes through equilibrium, how do their kinetic energies KA and KB compare?
(a) KA is half KB
(b) The comparison cannot be made without knowing the masses
(c) KA equals KB
(d) KA is four times KB