Forces and Elasticity Flashcards
Forces (14 cards)
What happens when you apply a force to an object?
It may cause the object to stretch, compress, or bend.
This implies that a single force is not enough to change the shape; multiple forces or a sufficient amount of force is required.
What is required for an object to change shape instead of just moving?
More than one force acting on the object.
If only one force acts, the object will move in the direction of that force.
Define ‘elastically deformed’.
An object is elastically deformed if it can return to its original shape and length after the force has been removed.
Examples include elastic materials like springs.
What are objects that can be elastically deformed called?
Elastic objects.
An example of an elastic object is a spring.
Define ‘inelastically deformed’.
An object is inelastically deformed if it does not return to its original shape and length after the force has been removed.
What happens when a force stretches or compresses an object?
Work is done and energy is transferred to the elastic potential energy store of the object.
If the object is elastically deformed, all energy is transferred to its elastic potential energy store.
What is the relationship between extension and force in a spring?
Extension is directly proportional to the load or force applied.
This means that as you increase the force, the extension increases proportionally.
What is the equation that relates force, spring constant, and extension?
F = ke.
Here, F is the force, k is the spring constant, and e is the extension.
What does the spring constant depend on?
The material that you are stretching.
A stiffer spring has a greater spring constant.
How does the equation F = ke apply to compression?
It works for compression where e is the difference between the natural and compressed lengths.
Compression is treated similarly to extension in this context.
What is the limit of proportionality?
The maximum force above which the extension is no longer proportional to the force.
This is indicated on a graph of force against extension at the point marked P.
What happens to the graph of force against extension when the limit of proportionality is exceeded?
The graph curves, indicating that extension is no longer proportional to force.
True or False: The relationship between force and extension remains linear at all force levels.
False.
The relationship only remains linear until the limit of proportionality is reached.
Fill in the blank: The extension of a stretched spring is directly proportional to the _______.
force applied.
