Density is given by the equation

- Density = mass x volume
- Density = Volume/mass
- Density = mass/volume
- Density = 1/2 x mass x volume

Which one of these is the correct SI unit for density?

- kilogram per cubic metre
- gram per cubic centimetre
- cubic metre per kilogram
- metre per cubic kilogram

In Physics, the word ELASTIC is defined as:

- A material that is bouncy.
- A material that is soft.
- How much load a material can carry before it is distorted.
- Ability of a material to regain its original shape after it is distorted.

A PLASTIC material is one that:

- is easily moulded.
- does not return to its original shape after it has been distorted.
- a material that is a polymer.
- a material that is a polymer, but made from the products of crude oil.

Which one of these statements is correct for Hooke's Law?

- Extension is directly proportional to force and the spring constant is measured in newtons per square metre.
- Extension is inversely proportional to force and the spring constant is measured in newtons per metre.
- Extension is directly proportional to force and the spring constant is measured in newtons per metre.
- Extension is proportional to the square of the force and the spring constant is measured in newtons per metre.

Which one of the following is true about a graph of force against extension for a material that obeys Hooke's Law.

- 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.
- The graph is a straight line that goes through the origin and the area gives the spring constant. The gradient gives the energy.
- 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.
- 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.

Stress in a material is defined as:

- the maximum load a material can take without breaking.
- Force per unit area
- Area per unit force
- The product of force and area.

Units for stress are pascals. 1 Pa =

- 1 Newton metre
- 1 Newton per metre
- 1 metre per Newton
- 1 Newton per square metre

The strain is:

- mass per unit length
- the extension divided by the original length.
- the extension divided by the stretched length.
- extension per unit stress

When loading and unloading a wire, we find that some energy is lost. Which one of the following statements is true?

- The lost energy is called hysteria and is the difference in the areas under the graph
- The lost energy is called hysteria and is the difference in the gradients of the graph
- The lost energy is called hysteresis and is the difference in the areas under the graph
- The lost energy is called hysteresis and is the difference in the gradients of the graph

The yield point in a stress-strain graph is the point at which:

- the point at which the wire starts to undergo plastic deformation
- the point at which further plastic deformation happens even when the load is reduced.
- the point at which plastic deformation occurs when there is zero load.
- the point at which the wire snaps

The Young Modulus is given by:

- E = stress x strain
- E = 1/2 x stress x strain
- E = strain/stress
- E = stress/strain

Which statement is true for a brittle material?

- Brittle materials are strong, but break after a lot of plastic deformation
- Brittle materials are strong, but break suddenly with little or no plastic deformation
- Brittle materials are weak, but break suddenly with little or no plastic deformation
- Brittle materials are strong, but break after a lot of plastic deformation

Which one of the following statements about the units for the Young's Modulus and strain is correct

- Young's Modulus has units of Pa and the strain is in metres
- Young's Modulus has units of Pa and the strain is in Newtons
- 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.

Which one of the following statements is true about the stress-strain graph?

- The gradient gives the Young Modulus and the area gives the strain energy.
- The gradient gives the Young Modulus and the area gives the strain energy per unit volume
- The area gives the Young Modulus and the gradient gives the strain energy.
- The area gives the Young Modulus and the gradient gives the strain energy per unit volume.