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Two soap bubbles A and B are kept in a closed chamber where the air is maintained at pressure 8 Nm ⁻² . The radii of bubbles A and B are 2 ~cm , respectively. Surface tension of the soap-water used to make bubbles is 0.04 Nm ⁻¹ . Find the ratio n_B n_A , where n_A and n_B are the number of moles of air in bubbles A and B , respectively. [Neglect the effect of gravity]

Correct answer

6

Step-by-step solution

Although not given in the question but we will have to assume that temperatures of A and B are same. aligned & n_B n_A = p_B V_B / R T p_A V_A / R T = p_B V_B p_A V_A &= p+4 s / r_A 4 / 3 (r_A )^3 (p+4 s / r_B ) 4 / 3 (r_B )^3 &(s= surface tension) aligned

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