The figure illustrates the flow of an ideal fluid through a pipe of circular cro
ID: 2123747 • Letter: T
Question
The figure illustrates the flow of an ideal fluid through a pipe of circular cross section, with diameters of 1cm and 2cm and with different elevations. Px is the pressure in the pipe, and Vx is the speed of the fluid at locations x = Q,R,S,T, or U.
image url: http://s21.postimg.org/evg0q7bh3/image.png
VU is .... VS
PR is .... PT
PS is .... PQ
VT is .... 0.5VU
Explanation / Answer
1. sorry, neglected the effect of pressure before,
VU = VS
reason : AU*VU = AS*VS
=> VU = VS
2. PR < PT
reason : AT>AR
=> VT<VR
=> PR<PT
3. PS < PQ
reason : (PE)S > (PE)Q
=> PS < PQ
4. VT < 0.5VU
reason : AT*VT = AU*VU
=> pi*2^2*VT = pi*1^2*VU
=> 4VT = VU
so VT = 0.25VU