SOLUTIONS – Ch. 14: 4-6 14.34.IDENTIFY:The volume flow rate is Av. SET UP:. . 30.750 m/sAv=2/4ADπ=EXECUTE:(a). 230.750 m/svD=3224(0.750 m/s )472 m/s(4.50 10 m)v−==×. (b)must be constant, so . 2vD112 2=222112(472 m/s)52.4 m/s3DDvv⎛⎞=⎜⎟⎝⎠. EVALUATE:The larger the hole, the smaller the speed of the fluid as it exits. 14.41.IDENTIFYand SET UP:Apply Bernoulli’s equation to points 1 and 2 as shown in Figure 14.41. Point 1 is in the mains and point 2 is at the maximum height reached by the stream, so 20.v=Figure 14.41 Solve for 1pand then convert this absolute pressure to gauge pressure. EXECUTE:111222pgyvyvρρρ++=Let The mains have large diameter, so 10,y=215.0 m.y=10.v≈Thus 122.py=+But 2a,pp=so 3251a2(1000 kg/m )(9.80 m/s )(15.0 m)1.47 10 Pa.pp gy−=== ×EVALUATE:This is the gauge pressure at the bottom of a column of water 15.0 m high. 14.89.IDENTIFY:Apply Bernoulli’s equation and the equation of continuity. SET UP:Example 14.8 says the speed of efflux is 2gh, where his the distance of the hole below the surface of the fluid.
This is the end of the preview. Sign up
access the rest of the document.