# What would hapen to coefficent of spring if we cut it

1. May 1, 2007

### reza

what would hapen to coefficent of spring if we cut it in to 2 equal parts?

2. May 1, 2007

### lalbatros

And what will you do with the parts, exactly?
Each of the part will have a double coefficient.
To stretch it to the same length as before, you will need to deform it twice as much.
(deformation= (final length)/(initial length))

3. May 2, 2007

### reza

I want to know why it became double

4. May 3, 2007

### reza

i mean why it's coefficient become twice i want logic answer
i want to know why K1=2K2 (if k1 is the first spring and k2 is belong to other spring-the second one-)

5. May 3, 2007

### Staff: Mentor

You can calculate the spring constant by considering k = F/x, where x is the amount the spring is stretched.

Imagine that you apply a force F to the full spring and it stretches an amount x. Now realize that the full spring is just two half-springs in series. How much does each half-spring stretch? What force does each half-spring exert? (Careful with that last question.)

6. May 4, 2007

### reza

the stretch of each one x/2
and the forces are equal (F1=F2)

7. May 4, 2007

In can be put mathematically like this. When you cut a spring in two equal halves then the value of spring cinstant doubles.

8. May 4, 2007

### Staff: Mentor

Exactly. Now calculate the new spring constant:
k' = Force/stretch = F/(x/2) = 2 F/x = 2k

Make sense?

9. May 5, 2007

### reza

I understand and thank you so much
but i want to know it's microscopic answer i mean what is the nature of spring constant (a physical answer not a mathematical answer)
can you give me brif answer or guid me a source to found it out