The viscous drag acting on a metal sphere of diameter $$1$$ mm, falling through a fluid of viscosity $$0.8$$ Pa-s with a velocity of $$2$$ ms–1 is nearly equal to:
1. $$15\times 10^{-3}~\text{N}$$
2. $$30\times 10^{-3}~\text{N}$$
3. $$1.5\times 10^{-3}~\text{N}$$
4. $$20\times 10^{-3}~\text{N}$$
Subtopic:  Stokes' Law |
59%
From NCERT
NEET - 2023
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The terminal velocity of a copper ball of radius $$5~\text{mm}$$ falling through a tank of oil at room temperature is $$10~\text{cm}~\text{s}^{-1}$$ . If the viscosity of oil at room temperature is $$0.9~\text{kg}~\text{m}^{-1}~\text{s}^{-1}$$, the viscous drag force is:
1. $$8.48 \times10^{-3}$$ N
2. $$8.48 \times10^{-5}$$ N
3. $$4.23 \times10^{-3}$$ N
4. $$4.23 \times10^{-6}$$ N
Subtopic:  Stokes' Law |
64%
From NCERT
NEET - 2022
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A small sphere of radius $$r$$ falls from rest in a viscous liquid. As a result, heat is produced due to the viscous force. The rate of production of heat when the sphere attains its terminal velocity is proportional to:
 1 $$r^3$$ 2 $$r^2$$ 3 $$r^5$$ 4 $$r^4$$
Subtopic:  Stokes' Law |
54%
From NCERT
NEET - 2018
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