A 0.45 m long guitar string, of cross-sectional area 1.0 10-6 m2, has Young's modulus Y = 2.20 109 N/m2. By how much must you stretch the string to obtain a tension of 20 N?
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Y = (FL)/(AΔL) or (F/A)/(ΔL/L) [where in first formula -> Y=Young's Mod., F=Force, A=Area, L=Length, ΔL=Change in length, in second formula -> F/A = Longitudnal Stress, ΔL/L = Longitudnal Strain]
So, putting all known values (Tension is force only):
--> 2.2 * 10^9 = (20*0.45)/(10^-6*ΔL)
--> ΔL = 9/(2.2 * 10^3)
--> ΔL = 4.09 * 10^-3 m or 0.409 cm or 4.09 mm.
So, putting all known values (Tension is force only):
--> 2.2 * 10^9 = (20*0.45)/(10^-6*ΔL)
--> ΔL = 9/(2.2 * 10^3)
--> ΔL = 4.09 * 10^-3 m or 0.409 cm or 4.09 mm.