Q. Water is moving with a speed of $5.18\ {ms}^{- 1}$ through a pipe with a cross-sectional area of $4.20\ {cm}^{2}$ . The water gradually descend 9.66 m as the pipe increase in area to $7.60\ {cm}^{2}$ . The speed of flow at the lower level is
A) $3.0\ {ms}^{- 1}$
B) $5.7\ {ms}^{- 1}$
C) $3.82\ {ms}^{- 1}$
D) $2.86\ {ms}^{- 1}$
Explanation
(d) $a_{1}v_{1} = a_{2}v_{2}$
$\Longrightarrow \ \ 4.20 \times 5.18 = 7.60 \times v_{2}$
$\Longrightarrow \ \ v_{2} = 2.86\ {ms}^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.