Step 1: Find Spring Constant (k)The spring stretches by 0.2 m when a 0.5 kg mass hangs from it.This means the force from the weight (m1g) equals the force from the spring (kx) :kx=m1gSo,k=xm1g=0.20.5×10=25N/mStep 2: Use the New MassThe new hanging mass is m2=0.25kg.Step 3: Find the New Time Period ( T )The time period of a mass-spring system is:T=2πkm2Substitute the values:T=2π250.25T=2π0.01T=2π×0.1=0.2πsStep 4: Calculate the Value Using π≈3.14 :T=0.2×3.14=0.628s