Equivalent Pipe

Q. A compound pipe (new cast iron) system consists of pipes of length 1800 m and diameter 50 cm, length 1200 m and diameter 40 cm and length 600 m and diameter 30 cm connected in series. The equivalent length of 40 cm diameter pipe will be nearly

1. 4300 m
2. 4400 m
3. 4500 m
4. 3600 m

Q. The length of a pipe is 1000 m and its diameter is 200 cm. If the diameter of an equivalent pipe is 40 cm, then its length is:

1. 4000 m
2. 32000 m
3. 20000 m
4. 8000 m

Q. If a single pipe of length L and diameter D is to be replaced by three pipes of same material, same length and equal diameter d (d < D), to convey the same total discharge under the same head loss, then d and D are related by

1. $D=\frac{d}{3^{1/5}}$
2. $D=\frac{d}{2^{5/3}}$
3. $D=\frac{d}{3^{2/3}}$
4. $D=\frac{d}{2^{3/2}}$

Q. A ${90}^{\circ }$ elbow bend pipe diameter is 100 mm and loss coefficient is 0.9. Pipe friction factor is 0.02. What is the equivalent length of the pipe?

1. 9 m
2. 2.25 m
3. 1.125 m
4. 4.5 m