Answer:
ΔL = 1.68 mm
σ = 84 MPa
Explanation:
Thermal expansion is:
ΔL = α ΔT L
Thermal stress is:
σ = α ΔT E
Given:
α = 1.2×10⁻⁵ /°C
E = 1.0×10⁵ MPa
ΔT = 80°C − 10°C = 70°C
L = 2 m
ΔL = (1.2×10⁻⁵ /°C) (70°C) (2 m)
ΔL = 0.00168 m
ΔL = 1.68 mm
σ = (1.2×10⁻⁵ /°C) (70°C) (1.0×10⁵ MPa)
σ = 84 MPa
Answer:
R = 4.75 lb (↑)
Explanation:
Number of books = n = 19
Weight of each book = W = 1 lb
Length of the bookshelf = L = 40 inches
We can get the value of the distributed load as follows
q = n*W/L = 19*1 lb/ 40 inches = 0.475 lb/in
then the reactions at 4 ends (supports) of the bookshelf are
R = (q/2)/2 = 4.75 lb
We can see the bookshelf in the pic.
Answer:
K
Explanation:
For installations where the nonlinear load is huge, most consulting engineers will specify K-rated transformers.