1. Chapter 7 - Holt Forces in Fluids

2. Section 1 pages 162-167 A fluid is any material that can _____ and that takes the shape of its container. Fluids include liquids, such as _________ and _________, gases such as ____________ and _________ ___________.

3. Fluids are able to flow because the particles in fluids, unlike the particles in solids can move easily _________ each other.

4. The following equation can be used to find the pressure, or rearranged to find force or area. Pressure = Force / Area The SI unit for pressure is the _______

5. Why are bubbles round?

6. Why do your ears ‘pop’ when you are in a plane taking off or in a car travelling down a steep mountain road?

7. The pressure caused by the weight of Earth’s atmosphere is called ___________ ___________. Fluids exert pressure __________ in all directions

8. Fluid pressure ___________ as depth increases. Fluids flow from areas of _________ pressure to areas of _________ pressure.

9. Pascall’s Principle states that a change in pressure at any point in an enclosed fluid will be __________ __________ to all parts of the fluid. __________ devices transmit changes of pressure through liquids.

10. Section 2 pages 168-172 Any object that is more dense that the surrounding fluid will ________. Any object that is less dense than the surrounding fluid will ________.

11. All fluids exert an upward force called __________ force, which is caused by differences in _________ pressure.

12. ______________ Principle states that the buoyant force on an object is equal to the weight of the fluid _________ by the object.

13. Section 3 pages 173 - 177 Bernoulli’s Principle states that fluid pressure decreases as the speed of a moving fluid _________.

14. Concerning flight. Wings are often shaped to allow airplanes (and birds) to take advantage of decreased pressure in moving air in order to achieve ____________.

15. ________ is an upward force that acts against ________. _______ opposes motion through fluids

16. Lift on an airplane is determined by _________ size and ________. Thrust is the forward motion produced by the __________ of an airplane.

17. questions 1. Compared with an empty ship, will a ship loaded with plastic-foam balls float higher or lower or the same level in water? Explain your answer.

18. 2. If an object weighing 50 N displaces a volume of water with a weight of 10 N, what is the buoyant force on the object? Show your equation and work.

19. 3. A helium-filled balloon will float in air because _______________________

20. 4. Where is warer pressure greater? At a depth of 1 m in an ocean, or, at a depth of 2 m in a small pond? Explain your answer.

21. Inside all vacuum cleaners is a high- speed fan. Explain how this fan causes dirt to be picked up by the vacuum cleaner.

22. Look at Interpreting Graphics page 181. Answer questions 21,22,23,24 concerning icebergs.

23. THE END