Answer:501.67 cm²
Explanation:We can use the formula for thermal expansion:
A₂= A₁(1+αΔ T)
Where:
A₁=500 cm²( initial area at0°C)
A₂= area at80°C( what we want to find)
α= coefficient of linear thermal expansion of copper(16.8 x10^-6/° C)
Δ T= change in temperature(80°C-0°C=80°C)
Pl ugging in the values, we get:
A₂=500 cm²(1+16.8 x10^-6/° C x80°C)
A₂=500 cm²(1+0.001344)
A₂=500 cm² x1.001344
A₂=501.67 cm²
Therefore, the area of the copper sheet at80°C is approximately501.67 cm².