Elasticity

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

Hooke's Law fails when a material reaches its:

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

A graph of extension against force for an elastic material is:

• A downward curve
• An upward curve
• A straight line from any point on the x and y axis
• A straight line from the origin

A spring has a spring constant of 5N/cm.  What is its extension when loaded with 15N?

• 4cm
• 5cm
• 3m
• 3cm

A spring has a spring constant of 5N/cm.  What is its extension when loaded with 15N?

• 4cm
• 5cm
• 3m
• 3cm

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

What type of force is shown inside of the picture?

• Tension

• Friction

• Elastic

• Gravitational

Which statement most accurately represents Hooke's Law?

• a) Extension of a spring is proportional to the force applied.
• b) Extension of a spring is proportional to the number of coils.
• c) Extension of a spring is inversely proportional to the force applied.
• d) Thickness of a spring wire is proportional to the force applied.

Spring constant is measured in

• N

• N/m

• m

The relationship between stretching force, F, with the extension, x, of a spring, is given by the equation: F = kx where k is the spring constant. What is the unit of k?

• N m^-1

• N m^-2

• kg m^-1

• kg m^-1