An object falling through a fluid is observed to have acceleration given by $a = g -bv$ where $g =$ gravitational acceleration and $b$ is constant. After a long time of release, it is observed to fall with constant speed. The value of constant speed is
A$\frac{g}{b}$
B$\frac{b}{g}$
C$bg$
D$b$
Medium
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A$\frac{g}{b}$
a Here, $a=g-b v$
When an object falls with constant speed $v_{c},$ its
acceleration becomes zero.
$\mathrm{g}-\mathrm{bv}_{\mathrm{c}}=0 \text { or } \mathrm{v}_{\mathrm{c}}=\frac{\mathrm{g}}{\mathrm{b}}$
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