Hooke's Law

Hooke's Law

All elastic materials behave as springs.

Multiple Choice

If F is force, k is spring constant and x is extension, Hooke's Law tells us that:

• F=k/x
• x=Fk
• k=Fx
• F=kx

Multiple Choice

A 25,000 N Car is supported by 4 springs.  If each spring is deflected by 0.040 m what is the spring constant? 

• 160,000 N /m
• 620,000 N/m
• 630,000 N/m
• 120,000 N/m

Multiple Choice

A force of F=500 N is applied to extend a spring.  What is the displacement x of the spring if its spring constant is k= 540 N/m?

• 0.96 m
• 0.93 M
• 1.3 m
• 1.1 m

Multiple Choice

What force should be applied to compress a spring by 0.013 m if its spring constant is k = 1900 N/m?

• 1880 N
• 24.7 N
• 1900 N
• 0.127 N

Multiple Choice

A spring has a spring constant of 330 N/m.  How far is the spring compressed if 150 N of force are used?

• 2.2 m
• 0.0014 m
• 5.0 m
• 0.45 m

Elastic Limit

• Hooke's Law usually only works for a range of displacements

• The limit where it stops working is known as the spring's Elastic limit

• This may be where the spring stretches out or breaks.

Multiple Choice

Hooke's Law fails when a material reaches its:

• breakdown
• elastic limit
• end of tether
• fracture stress

Multiple Choice

A stiff material has a:

• high spring constant
• low spring constant
• spring constant of any value
• spring constant which is difficult to predict

Multiple Choice

The data in the graph represents the extension of a spring. Calculate the spring constant using the equation:

Spring constant = Force ÷ Extension

• 2 N/m

• 0.5 N/m

• 60 N/m

• 20 N/m

Multiple Choice

What Quantity can you calculate from the graph and give the magnitude of that quantity.  

• distance 4.5 m
• Force 15 N
• spring constant 20 N/m
• spring constant 200 N/m

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