Question

A round steel plate with a diameter of 20 cm is supplied with heat in such a way that its temperature changes from 22 ° C to 150 ° C. How much does its area increase?

Answer 1

1.05×10⁻⁴ m²

Step-by-step explanation:

ΔA = 2 A₀ α ΔT,

where ΔA is the change in area,

A₀ is the initial area,

α is the linear expansion coefficient,

and ΔT is the change in temperature.

A₀ = π (0.20 m / 2)² = 0.0314 m².

For steel, α = 13×10⁻⁶ /°C.

ΔT = 150°C − 22°C = 128°C.

ΔA = 2 (0.0314 m²) (13×10⁻⁶ /°C) (128°C)

ΔA = 1.05×10⁻⁴ m²