An object falling through a fluid is observed to have acceleratio… - Vidyadip

MCQ

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

✓
$\frac{g}{b}$
B
$\frac{b}{g}$
C
$bg$
D
$b$

✓

Answer

Correct option: 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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