Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
The radius of a water pipe is 14.4cm. How fast ?
A. The radius of a water pipe is 14.4cm. How fast does the water flow in the pipe if the flow rate is Q = 396 L/min?
Assume 3 significant digits and MKS units of m/s.
B. A swimmer is at the bottom of a 3.99 meter deep pool that is filled with water. What is the force exerted on an eardrum if the area of the eardrum is 58.1 mm2?
Assume 3 significant digits and units of Newtons.
1 Answer
- 1 year agoFavorite Answer
Think of the pipe as a cylinder.
V = pi * r^2 * h
396 L/min = 396/60 L/s = 6.6 L/s
1 liter = 1000 cm^3
6.6 * 1000 cm^3 = pi * 0.144^2 * h cm^3
Solve for h
6.6 * 1000 / (pi * 0.144^2) = h
h = 6600 / (pi * 0.144^2)
h = 101313.91053303522531584035862834...
That's in cm
1013.139105.... meters per second
1010 m/s
Find the mass of a slug of water with a base of 58.1 mm^2 and height of 3.99 meters
V = 58.1 mm^2 * 3.99 meters
V = 58.1 mm^2 * 3990 mm
V = 581 * 399 mm^3
1 cm = 10 mm
0.1 cm = 1 mm
0.001 cm^3 = mm^3
V = 581 * 399 * 10^(-3) cm^3
Mass = Density * Volume
m = 1 gram/cm^3 * 581 * 399 * 10^(-3) cm^3
m = 581 * 299 * 10^(-3) grams
m = 581 * 299 * 10^(-6) kg
Force = mass * acceleration
F = 581 * 299 * 10^(-6) * 9.81 Newtons
F = 1704183.39 * 10^(-6) Newtons
F = 1.70418339 Newtons
To 3 sf
1.70 Newtons
