Q. 4

# An ideal fluid flows through a pipe of circular cross-section made of two sections with diameters 2.5 cm and 3.75 cm. The ratio of the velocities in the two pipes is

A. 9:4

B. 3:2

C. √3: √2

D. √2: √3

Answer :

Given:

Diameter of section1 = d_{1} = 2.5 cm

Diameter of section2 = d_{2} = 3.75 cm

According to the law of continuity,

Along a streamline,

Av=constant.

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