# AP® Physics 1 & 2

Free Version
Difficult

APPH12-SBXI1D

Fluid is flowing through a horizontal section of cylindrical pipe, where the cross-sectional radius changes from a radius $R$ in the narrower section of pipe, to a larger radius $2R$ in the wider section.

If the flow speed of the fluid in the narrower section of pipe is v, what is the flow speed of the fluid in the wider section of pipe?

A

$\dfrac{v}{4}$

B

$\dfrac{v}{2}$

C

$2v$

D

$4v$