Chapter 3 (C) - Hooke's Law Flashcards
2 types of materials
elastic
plastic
What is an ‘elastic’ material
Materials that when bent, return to their original shape
What happens if you bend an elastic material too much
Breaks or gets deformed
What is a ‘plastic’ material
Materials that when bent, keep their new shape; they don’t return to their original shape
What is the force applied to the spring known as
Load
What is the load for every 100 grams that is hung from a spring
why?
Load is 1 Newton
since ‘g’ is 10 N/kg , 0.1 kg would be 1 N
Define extension
Difference between a spring’s stretched and unstretched lengths
Describe an Extension Load graph
x axis : units
y axis : units
features
x axis - Loan
units - Newtons (N)
y axis - Extension
units - mm, cm, etc
graph:
straight line that is upward sloping and passes through the origin
Gradient is the same since its a straight line
What is the point ‘x’ on the graph
what is the point ‘e’
x: Limit of proportionality - until point X, extension is proportional to load
e: elastic limit - uptil E, the spring behaves as an elastic material and returns to its original shape. Beyond e (if load is greater than e’s load) the spring is left permanently stretched
What is hooke’s law
A material obeys hooke’s law when, below the elastic limit, the extension is proportional to load
What is the equation for load, extension, etc
F = K * x
f = load/force
k = spring constant
x = extension
What is the spring constant
the constant that relates the load and the extension for that particular spring/material
its essentially the slope
Describe graph:
till x
between x and e
after e
till x - straight line, direclty prop
between x and e - slightly curved
after e - starts sloping upwards considerably sharply
see page 66 atl one time for reference
