Please solve q 167?

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1 Answer
Apr 5, 2018

#0.98# m

Explanation:

Let us denote the density of the liquid and the material of the bowl by #rho_l# and #rho_b#, respectively. If the outer and inner radii of the hemispherical bowl are #R# and #r#, respectively, then (since the bowl is just floating)

  • the weight of the bowl #= 2/3 pi (R^3-r^3) rho_b g#
  • the buoyant force on the ball #= 2/3 pi R^3 rho_l g#

Hence

#2/3 pi R^3 rho_l g= 2/3 pi (R^3-r^3) rho_b g implies#

# 1-r^3/R^3 = rho_l/rho_b = (1.2times 10^3)/(2times 10^4) = 0.06 implies#

#(r/R)^3 = 0.94 implies r/R = root{3}{0.94}~~ 0.98#