How High Can a Tower of Sugar Cubes Be?

[pippintook]

Homework Statement

The Babblers have decided to build a tower that would reach the top of Rock Candy Mountain. For brick they used large sugar cubes ( = 1500 kg/m³). The compressive strength (stress) of sugar cubes is 6.0 MPa. How tall of a tower can the Babblers build?

Homework Equations

Stress = F/A = Y(ΔL/L₀)A

The Attempt at a Solution

I converted 6MPa to N/m² for 6,000,000 N/m², I just don't know how to find L. The A's cancel, leaving me with F = Y(ΔL/L₀), right? Is Y = 1500 kg/m^3?

 

[KLoux]

I'm not sure you're using the right equations... the stress relationship is OK (stress = F/A), but how is this related to the height? Show an equation that can relate the height of tower to some part of the stress equation.

-Kerry