COC Materials Science & Technology

Question 1

Which property describes a material's ability to return to its original shape after deformation without permanent change?

Accepted Answer

Elasticity

Answer

Elasticity is the material property that allows a substance to fully recover its original dimensions upon removal of the applied load.

Question 2

Carbon fiber composite materials used in O&P are reinforced with carbon fibers primarily to improve which mechanical property?

Accepted Answer

Stiffness-to-weight ratio

Answer

Carbon fiber composites have an exceptionally high stiffness-to-weight ratio, making them ideal for energy-storing prosthetic feet and lightweight orthotic shells.

Question 3

Thermoplastic materials used for custom orthotics are typically formed at temperatures between:

Accepted Answer

150–180°F (65–82°C)

Answer

Low-temperature thermoplastics commonly used for splints and orthotics soften and become moldable at 150–180°F, allowing direct patient molding.

Question 4

What is the primary advantage of using titanium over steel in prosthetic structural components?

Accepted Answer

Higher strength-to-weight ratio

Answer

Titanium offers a superior strength-to-weight ratio compared to steel, allowing structurally sound prosthetic components at significantly reduced mass.

Question 5

Viscoelastic materials exhibit which combination of properties?

Accepted Answer

Both viscous (time-dependent) and elastic (recoverable) behavior

Answer

Viscoelastic materials exhibit rate-dependent behavior, combining elastic recovery with viscous energy dissipation, as seen in gel liners and dynamic foot keel materials.

COC - Certified Orthotic and Prosthetic Practitioner Practice Test

COC - Certified Orthotic and Prosthetic Practitioner Practice Test

COC Materials Science & Technology