6. Deformation of solids

What is deformation?

Deformation is caused by tensile forces (stretching) or compressive forces (squeezing).

What is load?

Load is the force applied to an object.

What is extension?

Extension is the increase in length of a material from its original length.

What is compression?

Compression is the reduction in length of an object under compressive load.

What is the limit of proportionality?

The limit of proportionality is the point beyond which extension is no longer proportional to the force.

State Hooke’s Law.

F = kx, where F is force, x is extension, and k is the spring constant.

What is stress and its formula?

Stress (σ) is force per unit cross-sectional area that acts at right angles to a surface.
σ = F/A
Unit: Pascals (Pa) or N/m².

What is strain and its formula?

Strain (ε) is extension per original length.
ε = x/L
No unit.

Define Young Modulus and give its formula.

Young Modulus is the stress in the material ÷ strain.
E = σ/ε
Unit: Pascals (Pa).

How do you determine the Young Modulus of a metal in wire form?

Measure extension of a wire under various loads, then use formulas to calculate stress and strain to calculate the Young Modulu