Physics 1029A/B Chapter Assignment: Physics 1029A/B Chapter : A2 Waves and Sounds Answers

A person, with his ear to the ground, sees a huge stone striketheconcrete pavement. A moment later two sounds are heard fromtheimpact: one travels in the air and the other in the concrete,andthey are 2.0 s apart. How far away did theimpact occur? SeeTable 12-1
1 m

1. The record for the fastest marathon run is 26.164 miles in 2.08hours. If the runner were a progressive wave, how quickly would hebe traveling in m/s?

2. You have been asked to help in the design of a new powergenerator which harnesses the power of progressive waves travelinginto shore. The power generator has to be located in shallow waterright at the coastline, and the engineers have informed you thatthe machine will only operate at peak capacity when the incomingwave speeds are 6.5m/s. How deep do you dredge to ensure that thewaves coming in from the open ocean will keep the power generatorworking at peak capacity? Which wavelengths will diminish the powergenerator's efficiency?

3. On 11 March 2011, a 9.0 magnitude earthquake occured in thePacific Ocean, centered 99 kilometers SE from Kesennuma, Japan.Assuming that the water depth above the earthquake epicenter was2200 meters, how much time did the residents of Kesennuma (andnearby coastal villages) have to get to higher ground before theTsunami hit the coast?

4. The Earth's orbit around the sun is not a perfect circle; it is,in fact, elliptical. In January, the Earth is 147 million kiometersfrom the Sun. In July, the Earth is 152 kilometers from the Sun. Ifthe tide-generating force from the Sun is F(sun)=1/r^2, how do youthink the amplitude of the spring tides in winter would comparewith those of the spring tides in the summer (assuming northernhemisphere seasonality)?

Could you please correct the English and the science behindthismethod that I have written. I am rating LIFESAVER forgoodcorrection. Thank you

1. 1. Measure the diameterofthe loose bead using the micrometer.

2. 2. Measure the weight oftheloose bead using the electronic scale.

3. 3. Measure the weight ofthemeasuring cylinder.

4. 4. Fill one of themeasuringcylinders (A), (B) or (C) with 100 ml of engine oil.

5. 5. Measure the weight ofthatmeasuring cylinder and the oil it contains.

6. 6. Fill each of themeasuringcylinders (A), (B) and (C) with more than 100 ml ofengine oil byabout 20ml.

7. 7. Set the refrigerator atatemperature of 15°C, then place measuring cylinder (A)into it forhalf an hour or so to get it to the temperatureneeded. After thatremove measuring cylinder (A) fromrefrigerator.

8. 8. Instantly place theloosebead into measuring cylinder (A). Then measure the time ittakesthe loose bead to travel the distance between 75 ml to 25mlmarkings on the cylinder. Record your results in a table.

9. 9. Measure and recordtheroom temperature.

10. 10. Repeat step3using measuring cylinder (B).

11. 11. Placemeasuringcylinder (C) on a hot plate and heat it to a temperatureof40°C.

12. 12. Repeat step3using measuring cylinder (C).

Each of step 7,8,10, 11 and 12.