Unit 11 Properties of Materials
1. Density is given by the equation
A.
Density = mass x volume
B.
Density = Volume/mass
C.
Density = mass/volume
D.
Density = 1/2 x mass x volume
2. Which one of these is the correct SI unit for density?
A.
kilogram per cubic metre
B.
gram per cubic centimetre
C.
cubic metre per kilogram
D.
metre per cubic kilogram
3. In Physics, the word ELASTIC is defined as:
A.
A material that is bouncy.
B.
A material that is soft.
C.
How much load a material can carry before it is distorted.
D.
Ability of a material to regain its original shape after it is distorted.
4. A PLASTIC material is one that:
A.
is easily moulded.
B.
does not return to its original shape after it has been distorted.
C.
a material that is a polymer.
D.
a material that is a polymer, but made from the products of crude oil.
Unit 11 Properties of Materials
5. Which one of these statements is correct for Hooke's Law?
A. Extension is directly proportional to force and the spring constant is
measured in newtons per square metre.
B.
Extension is inversely proportional to force and the spring constant is
measured in newtons per metre.
C.
Extension is directly proportional to force and the spring constant is
measured in newtons per metre.
D. Extension is proportional to the square of the force and the spring
constant is measured in newtons per metre.
6. Which one of the following is true about a graph of force against extension for
a material that obeys Hooke's Law.
A.
The graph is a straight line that goes through the origin and the
gradient gives the spring constant. The area under the graph gives the
energy.
B.
The graph is a straight line that goes through the origin and the area
gives the spring constant. The gradient gives the energy.
C. The graph is a straight line that does not pass through the origin. The
gradient gives the spring constant. The area under the graph gives the
energy.
D.
The graph is a curve that goes through the origin and the gradient
gives the spring constant. The area under the graph gives the energy.
7. Stress in a material is defined as:
A.
the maximum load a material can take without breaking.
B.
Force per unit area
C.
Area per unit force
D.
The product of force and area.
Unit 11 Properties of Materials
8. Units for stress are pascals. 1 Pa =
A. 1 Newton metre
B.
1 Newton per metre
C.
1 metre per Newton
D.
1 Newton per square metre
9. The strain is:
A.
mass per unit length
B.
the extension divided by the original length.
C.
the extension divided by the stretched length.
D.
extension per unit stress
10. When loading and unloading a wire, we find that some energy is lost. Which
one of the following statements is true?
A.
The lost energy is called hysteria and is the difference in the areas
under the graph
B.
The lost energy is called hysteria and is the difference in the gradients
of the graph
C. The lost energy is called hysteresis and is the difference in the areas
under the graph
D.
The lost energy is called hysteresis and is the difference in the
gradients of the graph
Unit 11 Properties of Materials
11. The yield point in a stress-strain graph is the point at which:
A. the point at which the wire starts to undergo plastic deformation
B. the point at which further plastic deformation happens even when the
load is reduced.
C. the point at which plastic deformation occurs when there is zero load.
D. the point at which the wire snaps
12. The Young Modulus is given by:
A.
E = stress x strain
B.
E = 1/2 x stress x strain
C. E = strain/stress
D. E = stress/strain
13. Which statement is true for a brittle material?
A.
Brittle materials are strong, but break after a lot of plastic deformation
B.
Brittle materials are strong, but break suddenly with little or no plastic
deformation
C.
Brittle materials are weak, but break suddenly with little or no plastic
deformation
D.
Brittle materials are strong, but break after a lot of plastic deformation
Unit 11 Properties of Materials
14. Which one of the following statements about the units for the Young's
Modulus and strain is correct
A.
Young's Modulus has units of Pa and the strain is in metres
B.
Young's Modulus has units of Pa and the strain is in Newtons
C.
D.
Young's Modulus has units of Pa and the strain is in metres to the
minus one
Young's Modulus has units of Pa and the strain has no units
15. Which one of the following statements is true about the stress-strain graph?
A.
The gradient gives the Young Modulus and the area gives the strain
energy.
B.
The gradient gives the Young Modulus and the area gives the strain
energy per unit volume
C.
The area gives the Young Modulus and the gradient gives the strain
energy.
D.
The area gives the Young Modulus and the gradient gives the strain
energy per unit volume.