Question

An ideal mass less spring is fixed to the wall at one end, as shown. A block of mass M attached to the other end of the spring oscillates with amplitude A on a friction less, horizontal surface. The maximum speed of the block is v_m. The force constant of the spring is

(A) Mg/A

(B) Mgv_m/2A

(C) Mv²_m/2A

(D) Mv²_m/A²

(E) Mv²_m/2A²

Answer 1

Correct option (D) Mv²_m/A²

Use energy conservation K=U_sp ½ mv_m² = ½k ∆x², with ∆x = A, solve for k.