Two pipes of same length and diameters d and 2d respectively are connected in series. The diameter of an equivalent pipe of same length is

A. 22.5 m/sec. B. 33 m/sec. C. 40 m/sec. D. 90 m/sec.

A. the weight of the body B. more than the weight of the body C. less than the weight of the body D. weight of the fluid displaced by the body

A. $${\text{p}} = {\text{T}} \times {\text{r}}$$ B. $${\text{p}} = \frac{{\text{T}}}{{\text{r}}}$$ C. $${\text{p}} = \frac{{\text{T}}}{{2{\text{r}}}}$$ D. $${\text{p}} = \frac{{2{\text{T}}}}{{\text{r}}}$$

A. cannot be subjected to shear forces B. always expands until it fills any container C. has the same shear stress.at a point regardless of its motion D. cannot remain at rest under action of any shear force