Does Compressing and Stretching a Spring Require Equal Force?

[gobbledygook]

Does it take the same amount of force to compress a spring 1cm as it does to stretch it 1cm?

Is it dependent on the type of spring?

If so, what kind of spring would exhibit properties similar to what I have posted above?

Is the spring constant, k, where F= -kx only used for spring compression, or can it be used interchangeably for both spring stretching and compression?

 

[tiny-tim]

welcome to pf!

hi gobbledygook! welcome to pf!

in exam questions, springs always obey Hooke's Law (F = -kx)

and yes it applies to both stretching (extension) and compression

(whether it applies accurately to all real-life springs, i have no idea! )

 

[AlephZero]

(whether it applies accurately to all real-life springs, i have no idea! )

It doesn't. It is true for many types of real-life springs, but you can make the relation between force and displacement pretty much anything you like by designing the right sort of spring.

One example of when it isn't true a long coil spring that would "buckle" when you try to compress it, and the force needed to compress it would be very small.

Another example is a coil spring that is made with the coils touching each other, so you can't compress it at all, but you can stretch it easily.

But tiny-tim is right - you can assume it is true in physics or engineering "homework" type questions, unless the question tells you to assume something different.

 

[gobbledygook]

Thanks Tim!

I am actually trying to find the spring constant of the launcher that I built.

Here are some photos of my spring launcher

 

[PJC01]

I would like to clarify that the amount of force required to compress or stretch a spring is not always equal for a given distance. The force required depends on the properties of the spring, such as its material, shape, and size. Therefore, it is not safe to assume that it takes the same amount of force to compress a spring 1cm as it does to stretch it 1cm.

The type of spring does play a significant role in its stretching and compression properties. For example, a coil spring will behave differently compared to a leaf spring when subjected to the same amount of force. The coil spring will compress more easily than it will stretch, while the leaf spring will stretch more easily than it will compress.

The properties described in the question are similar to those of a linear spring, where the force required to stretch or compress the spring is directly proportional to the distance. This type of spring is commonly used in everyday objects such as mattresses, trampolines, and shock absorbers.

The spring constant, k, is a measure of the stiffness of a spring and is used in the equation F= -kx, where F is the force applied, k is the spring constant, and x is the distance the spring has been stretched or compressed. This equation applies to both spring stretching and compression, as long as the spring is behaving in a linear manner. However, for non-linear springs, such as those with varying thickness or shape, the equation may not be applicable.

In conclusion, the amount of force required to compress or stretch a spring is not always equal, and it depends on the properties of the spring. The type of spring also plays a significant role in its stretching and compression properties. The spring constant, k, can be used interchangeably for both spring stretching and compression, as long as the spring is behaving in a linear manner.