Calculate the force a piano tuner applies to stretch a steel piano wire 8.00 mm, if the wire is originally 0.850 mm in diameter and 1.35 m long.

672N

Explanation:

The steel can be modeled in a certain range of applied force as an elastic element, by which we can use the following equation, which is originally from the hooke law that indicates that all material tends to recover its original form after the application of a force

where

E=young modulos=200.000Mpa

A= Cross-sectional area

=

L1=leght=1.35m=1350mm

L1-L2= deformation=8mm

solving

this could be newton#'s law of cooling. the cooling curve is exponential

the answer to this is proletariats.

hope this : )