Quiz 18

1. Archimedes principle states that

A. an object immersed in a fluid is acted upon by an upward force equal to the weight of the object.
B. an object immersed in a fluid is acted upon by a downward force equal to the weight of the object.
C. An object sinks in a fluid if its density is greater than the density of the fluid.
D. an object immersed in a fluid is acted upon by an upward force equal to the weight of the displaced fluid.
E. the pressure exerted by a fluid increases with depth

2. An object will float in a fluid partially immersed if

A. its density is less or equal to the density of the fluid
B. its density is less than the densty of the fluid.
C. its density is greater than the density of the fluid.
D. its density is equal to the density of the fluid
E. its density is greater or equal to the density of the fluid

3. An object of volume 6e-6 m 3 and density 7000 kg ⁄ m ³ is immersed inside a fluid of density 4500 kg ⁄ m ³. Calculate the force exerted by the fluid on the object.

A. 0.392 N
B. 0.134 N
C. 0.265 N
D. 0.435 N
E. 0.185 N

4. An object of volume 9e-4 m 3 is immersed in a fluid of density 7500 kg ⁄ m ³. If the weight of the object inside the fluid is 9 N, calculate the density of the object.

A. 8520.408 kg ⁄ m ³
B. 10510.527 kg ⁄ m ³
C. 16063.91 kg ⁄ m ³
D. 4986.588 kg ⁄ m ³
E. 7369.11 kg ⁄ m³

5. An object of density 725 kg ⁄ m ³ is floating in a fluid of density 1750 kg m ³. Calculate the percentage of its volume immersed in the fluid.

A. 13.046 %
B. 18.017 %
C. 65.621 %
D. 41.429 %
E. 48.701 %

6. An object of volume 5e-5 m ³ is floating in a fluid of density 5000 kg ⁄ m ³ with 3.5e-5 m ³ of its volume exposed above the surface of the fluid. Calculate the density of the object.

A. 1260.905 kg ⁄ m ³
B. 2062.413 kg ⁄ m ³
C. 1874.41 kg ⁄ m³
D. 1500 kg ⁄ m ³
E. 2454.498 kg ⁄ m ³

7. Tube 1 and tube 2 of cross-sectional radii of 0.16 m and 0.15 m respectively are connected together. When a fluid flows through these tubes, calculate the ratio of the speed of the fluid in tube 2 to the speed of the fluid in tube 1.

8. A tube of cross-sectional-radius 0.15 m is connected with a tube of cross-sectional radius 0.18 m. If the speed of a fluid in the 0.15 m cross-sectional radius tube is 21 m ⁄ s, calculate the speed of the fluid in the 0.18 m cross-sectional radius tube.

A. 20.477 m ⁄ s
B. 14.583 m ⁄ s
C. 2.897 m ⁄ s
D. 16.849 m ⁄ s
E. 4.634 m ⁄ s

9. Two tubes of different cross-sectional radii are connected horizontally. A fluid of density 2250 kg ⁄ m ³ enters the first tube with a speed of 1.5 m ⁄ s. The cross-sectional radius of the first tube is 0.02 m and that of the second tube is 0.14 m. If the pressure of the fluid in the first tube is 1e4 Pa, calculate the pressure of the fluid in the second tube.

A. 7450.487 Pa
B. 3042.588 Pa
C. 9325.293 Pa
D. 12530.196 Pa
E. 16264.237 Pa

10. Two tubes of different cross-sectional radii are connected together with the first tube elevated 0.6 m above the second tube. A fluid of density 3500 kg ⁄ m ³ enters the first tube with a speed of 0.25 m ⁄ s. The cross-sectional radius of the first tube is 0.09 m and that of the second tube is 0.13 m. If the pressure of the fluid in the first tube is 3e3 Pa, calculate the pressure of the fluid in the second tube.

A. 11135.498 Pa
B. 41538.381 Pa
C. 43990.098 Pa
D. 23664.25 Pa
E. 20711.105 Pa

Quiz 18: