A uniform spring whose unstretched length is l, has a force constant K. The spring is cut into two pieces of unstretched length l1 and l2 , where l2l1=n, n being an integer. Now a mass m is made to oscillate with first spring. The time period of its oscillation would be
Since k∝1l∴k1k2=l2l1=n
⇒k1=nk2
Now l=l1+l2⇒1k=1k1+1k2⇒1k=1k1+nk1
⇒k1=(n+1)k∴T=2π√mk1=2π√m(n+1)k