Unit 6: Deformation of Solids

Deformation
> caused by c__ & t__ forces

compressive, tensile

Point A is

limit of proportionality

From O → A, F = __
> k measures the s__ of a s__
> series: 1/k = _/_ + _/_… ;; parallel: k = _ + _… (opp of circuit resistance)

kx, stiffness, spring, 1/k1, 1/k2, k1, k2

__ u__ = w__ done in s__
> so W = __ = __ (as F=kx)
> limit of p__ is when x is no longer p__ to l__ (curves)

area under, work, stretching, 1/2Fx, 1/2kx^2, proportionality, proportional, load

O → A is __ deformation: when f__ r__, obj. r__ to o_ s__
> beyond ts is __ deformation: w__ r__ to o_ l__

elastic, force removed, returns, og shape, plastic, wont return, og length

Hooke’s Law: p__ t__ e__ l__ i_ n__ e__, e__ o_ a_ o__ i_ p__ t_ a__ f__

provided the elastic limit is not exceeded, extension of an obj is proportional to applied force

Stress: f__ p__ u__ c__-s__ a__ o_ _ w__

force per unit cross-sectional area of a wire

Stress formula σ =

F/A

Strain: e__ p__ u__ l__

extension per unit length

Strain formula ε =

x/L

Unit of stress: __ or Pa
Unit of strain: __ __
Unit of Young modulus: __ or Pa

Nm^-2, no unit, Nm^-2

Young modulus: s__ i_ _ m__ d__ b_ s__

stress in a material divided by strain

Young modulus formula E = __/__ = __/__ x __/__

stress/strain, F/A, L/x

Gradient of stress vs strain graph

Young modulus

Finding Young modulus of a wire
> measure d__ w/ micrometer
> Take values of F & _ & plot a g__ to find F/x (g__)
> E = stress/strain = F/A x L/x = _/_ x _/_
>> find A via πr² = π(1/2 x _)² = _/_πd²
>> so E = F/x x __/πd² (as u divide a fraction)

diameter, x, graph, gradient, F/x, L/A, d, 1/4, 4L

> a__ under curve = e__
> s__ area & r__ area are diff
> this diff is e__ r__ as h__

area, energy, stretched, released, energy released, heat