Studiot, I like your explanation (and Doc as well).
Because this is presented as a statics problem the mass is gently lowered, and some external magical force is slowly lowering it down (removing the energy (kinetic, perhaps)) so that the work done by the springs is less than the change in...
To be at equilibrium, the restoring force (F = kx) should be equal to the gravitational force from the object (F = mg), right?
And the original problem was stated..
A 5 * 10^5 Newton block lies on top of a spring with spring constant k_1 = 5.25 * 10^5 N/m.
Once the first spring compresses...
What am I missing here?...
If you place a mass on a spring, the change in potential energy of the mass should equal the stored potential energy in the spring, correct?
so PE = U
PE = mgh = Fx (F = force = mg, h = change in spring length x)
U = 1/2 k*x^2
Hooke's law: F=-kx, so...