The total mechanical energy of a spring-mass system in simple harmonic motion is E= 1/2 m w^2 .A^2.Supposethe oscillating particle isreplacedby another particle ofdoublethemass whilw thw amplitude remains the same .the new mechanical energy will be--

Here, mass becomes double, but angular frequency is also affected, which depends on mass.
Angular frequency becomes times.
So, Net change = 4 times.

it will remain the same because the frequancy will decrease by 2 and the mass increase by 2 so the net change is zero