Peter M. answered 11/21/23
AP Physics 1 & 2, IB Physics. Engineer with 30 years teaching Physics
This can be solved by using conservation of energy.
The mass initially has kinetic energy, which is converted to the Potential Energy of the spring AND gravitational Potential Energy.
1/2 mv2 = 1/2 kx2 + mgh h and k are the same.
One equation, one unknown.
Solve for m.