QUIZ 7 Chapters 11, 12 and 13 and 15 |
Below are sample problems from Ch. 13 for Quiz 7. I have also included at the bottom some problems from Chapter 11 and 12 to help prep you for Tuesday's Quiz 7 , which could also include material from your corrected Quiz 6 (See the link "Q6" on the syllabus page.) . We will spend a little time reviewing the homework and sample quiz problems before the quiz is administered. I assume you have been reading CH. 11, 12, and 13, so by now doing these problems should be natural. I will also provide homework problems from Chapter 13, but the sample quiz should give you a fresh head start. |
1. A solid box of volume 1.0 m^{3} is completely submerged and sits at rest the bottom of a pond of water. The density of water is 1000 kg/m^{3}. What is the magnitude of the buoyant force on the box? |
a. 98 N |
b. 9800 N |
c. 980000 N |
d nota |
2. What is the direction of the buoyant force on the box of the previous problem? |
a. downward |
b. upward |
c. leftward |
d rightward |
3. In the previous problem, the box sits at the bottom of the pond because |
a. the box density is greater than the density of water. |
b. the box density is equal to the density of water. |
c. the box density is less than the density of water. |
d. nota |
4. A solid box of volume 1.0 m^{3} is partially submerged and floats with the top of the box above the surface of a pond of pure water. The density of water is 1000 kg/m^{3 } . One half of the volume of the box is submerged under the water surface. What is the magnitude of the buoyant force on the box? |
a. 19600 N |
b. 49 N |
c. 4900 N |
d. 1960000 N |
e. nota |
5. In the previous problem, what direction is the buoyant force on the floating box? |
a. up |
b. down |
c. nota |
6. In the previous problem, what direction is the weight of the floating box? |
a. up |
b. down |
c. nota |
7. In the previous problem, the box floats because |
a. the box density is equal to the density of water. |
b. the box density is greater than the density of water. |
c. the box density is less than the density of water. |
d. nota |
8. Referring to the the previous problem, what is the density of the half-submerged box? |
a. 2000 kg/m^{3} |
b. 500 kg/m^{3} |
c. 1000 kg/m^{3} |
d. nota |
9. A scrap of iron is thrown overboard from inside a ship. The buoyant force on the ship will |
a. decrease |
b. increase |
c. remain the same |
d. nota |
10. In the previous problem, after the scrap is thrown overboard, the top of the ship will be |
a. farther above the surface of the water. |
b. closer to the surface of the water. |
c. the same distance from the surface of the water. |
d. nota |
11. What is the water pressure 20 m below the surface of a lake of
water? The density of water is 1000 kg/m^{3 } . For this problem's computation, you may assume that g = 10 m/s^{2}. |
a. 100000 N/m^{2} |
b. 100000 N |
c. 200000 N |
d. 200000 N/m^{2} |
e. nota |
12. In the previous problem, if you include atmospheric pressure, the answer will |
a. increase |
b. decrease |
HOMEWORK PROBLEMS FROM WHICH QUIZ 7 COULD ALSO BE DERIVED ARE LISTED BELOW: |
CH.11: EXERCISE 1, 2, 8, 9, 17, 27 |
CH 12: EXERCISE: 10, 12, 13, 16 |
CH 13: EXERCISE: 4, 11, 14, 15, 16, 23, 24, 25, 29, 30, 31, 32, 37, 39, 40, 42, 56 ( HINT SEE SECTION ON PASCALS PRINCIPLE. This principle helps us understand hydraulic lifts or the brakes on 18 wheel big rigs. |