Q. 14.13 (b) Figure 14.26 (a) shows a spring of force constant k clamped rigidly at one end and a mass m attached to its free end. force applied at the free end stretches the spring. Figure 14.26 (b) shows the same spring with both ends free and attached to a mass m at either end. Each end of the spring in Fig. 14.26 (b) is stretched by the same force .
(b) If the mass in Fig. (a) and the two masses in Fig. (b) are released, what is the period of oscillation in each case?
(a) In Fig, (a) we have
F=-kx
ma=-kx
(b) In fig (b) the two equal masses will be executing SHM about their center of mass. The time period of the system would be equal to a single object of the same mass m attached to a spring of half the length of the given spring (or undergoing half the extension of the given spring while applied with the same force)
Spring constant of such a spring would be 2k
F=-2kx
ma=-2kx