Deformation Of Solids

What is the correct unit for strain?

• Pa

• Nm^-2

• No unit

• Nm²

Select all the correct units for stress.

• Pa

• Nm^-2

• Nm²

• No unit

The Young's Modulus is defined as...

• The gradient of a stress strain graph

• The energy required to stretch a material.

• Stress/Strain

• Force/Extension.

Tensile Strain is

• $\frac{Increase\ in\ length}{original\ length}$

• $\frac{decrease\ in\ length}{original\ length}$

• $\frac{change\ in\ volume}{original\ volume}$

• all of the answer

Hooke's law states that

• the extension is proportional to the load when the elastic limit is not exceeded

• the extension is inversely proportional to the load when the elastic limit is not exceeded

• the extension is independent of the load when the elastic limit is not exceeded

• load is dependent on extension

If the length of wire is stretched by a load is doubled, then it's Young's modulus will be

• doubled

• halved

• becomes four times

• unaffected

Which of the following material is the most elastic?

• rubber

• copper

• brass

• steel

What is represented by the gradient of a graph of force (vertical axis) against extension (horizontal axis) for a wire obeying Hooke’s law?

• elastic limit

• spring constant

• stress

• Young modulus

What is the formula for Young Modulus?

•  $\Upsilon=\frac{Fl}{Ae}$  

•  $F=\frac{YA}{le}$  

•  $l=\frac{F}{A}$  

• no formula
  

What is the area under graph for stress versus strain .....

• spring constant, k

• strain energy per unit volume,

• strain energy, U

• elongation, e

• no area under graph