A ball rises to surface at a constant velocity in a liquid whose density is $4$ times greater than that of the material of the ball. The ratio of the force of friction acting on the rising ball and its weight is
A$3 : 1$
B$4 : 1$
C$1 : 3$
D$1 : 4$
Medium
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A$3 : 1$
a $\mathrm{F}_{\mathrm{B}}=\mathrm{F}_{\mathrm{v}}+\mathrm{F}_{\mathrm{G}}$
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