question_answer

When a tension F is applied the elongation produced in uniform wire of length l and radius r is e. When tension 2f is applied the elongation produced in another uniform wire of length 21 and radius 2r made of same material is:

A)  0.5 e                                    

B)  1.0 e

C)  1.5 e                                    

D)  2.0 e