# What is the length of the spring

#### tnutty

1. Homework Statement

Two identical weights of mass m hang motionless
from massless strings attached to the two ends of a
spring, as shown in the figure. The spring constant
of the spring is k. What is the length of the spring,
if its relaxed length is L0?

2. Homework Equations
f = -kx
f = ma

3. The Attempt at a Solution

2t = -kx

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#### Tom Mattson

Staff Emeritus
Gold Member
Re: spring

Two identical weights of mass m hang motionless
from massless strings attached to the two ends of a
spring, as shown in the figure.
Could you please either scan and attach the figure, or at least describe it?

3. The Attempt at a Solution

2t = -kx
Where did the "t" come from?

#### Delphi51

Homework Helper
Re: spring

No picture - can't tell what is going on from the written description.

#### Tom Mattson

Staff Emeritus
Gold Member
Re: spring

OK, so where does t come from?

#### tnutty

Re: spring

The picture sort of looks like this ;

______springIsHereOntheTable_______
|.....ignore these dots......................|
|..................................................|
|..................................................|<-those lines at the end are a string.
m1...............................................m2

so the spring is on a table and attached to the left if it is a string which passes a
massless pug at the corner of the table and m1 is hanging on that string at the left
side of the table and m2 is attached to the string on the right side which is also hanging
on the string.

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