Question

Molten aluminium was poured in a sand mould and the thickness of the solid skin formed after 20 seconds and 50 seconds were found to be 3 mm and 4.5 mm respectively. What would be the thickness of the solid skin at the end of 100 seconds after pouring?​

Answer 1

Given Molten aluminium was poured in a sand mould and the thickness of the solid skin formed after 20 seconds and 50 seconds were found to be 3 mm and 4.5 mm respectively. What would be the thickness of the solid skin at the end of 100 seconds after pouring?​

We know that skin thickness is given by

                   t = t ₁√z + t₂

                 3 = t₁ √20 + t₂

               3 = 4.472 t₁ + t₂--------(1)

  Similarly we have

            4.5 =  t₁√50 + t₂

           4.5 = 7.07 t₁ + t₂---------(2)

Solving (1) and (2) we get

         4.472 t₁ + t₂ = 3

         7.07 t₁ + t₂ = 4.5

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   - 2.598 t₁ = - 1.5

  So t₁ = 0.577

      t₂ = 0.418

Substituting these values in the above equation we get

t = t₁√z + t₂

t = 0.577 x √100 + 0.418

t = 6.188 mm

       

Answer 2

Answer:

t=6.188mm

will be the correct answer hope it helps you