Problem P. 4165. (May 2009)
P. 4165. Find the mass of that steel wire, which stores elastic potential energy of 10 J when it is expanded. The tensile strength of steal is 900 MPa. Its Young modulus is 210 GPa.
(4 pont)
Deadline expired on 11 June 2009.
Statistics:
91 students sent a solution.  
4 points:  74 students. 
3 points:  3 students. 
2 points:  6 students. 
1 point:  5 students. 
Unfair, not evaluated:  3 solutions. 
