- Joined
- Sep 7, 2013
- Messages
- 804
- Reaction score
- 173
If a spring has more coils, is that weakening or strengthening the spring constant?
Springs
- Thread starter orangeman25
- Start date
- Joined
- Nov 20, 2008
- Messages
- 120
- Reaction score
- 4
The spring constant decreases.
Think about Young's Modulus (E)
E = tensile strength/tensile stress = Force per Area/Extension per Length = (F/A)/(x/l) = Fl/xA
if
E = Fl/xA
then
F = (EA/l)x = kx
so
k = EA/l
if you increase the length by adding coils, your k decreases by the length corresponding to the number of coils added. With this same logic, if you cut the coil into 2 parts, you will increase k by 2
Think about Young's Modulus (E)
E = tensile strength/tensile stress = Force per Area/Extension per Length = (F/A)/(x/l) = Fl/xA
if
E = Fl/xA
then
F = (EA/l)x = kx
so
k = EA/l
if you increase the length by adding coils, your k decreases by the length corresponding to the number of coils added. With this same logic, if you cut the coil into 2 parts, you will increase k by 2
