Answer:
diameter = 5.78 cm .
Explanation:
According to Pascal's law, pressure will be equally transferred from smaller to larger cylinder.
Let the radius of larger cylinder be r cm
cross sectional area = π r²
pressure created on larger cylinder = 1.1 x 10⁴ / π r²
This pressure must be equal to 420 N / cm²
1.1 x 10⁴ / π r² = 420
r² = 8.34
r = 2.89 cm
diameter = 5.78 cm .