SOLVE STEP BY STEP WITHOUT ARTIFICIAL INTELLIGENCE A ship is located in a certain region of the ocean, conducting research that requires knowledge of the sea depth at that point. To do so, it emits a signal with a wavelength of 40 m and a frequency of 30 Hz. If the signal is detected by the ship's radar 8 seconds later, what is the depth of the sea in that region?

Check Your Understanding Figure 1.4 says the mass of the atmosphere is 1019kg . Assuming the density of the atmosphere is 1kg/m3 , estimate the height of Earth’s atmosphere. Do you think your answer is an underestimate or an overestimate? Explain why. How many piano tuners are there in New York City? How many leaves are on that tree? If you are studying photosynthesis or thinking of writing a smartphone app tot piano tuners, then the answers to these questions might be of great interest to you. Otherwise, you probably couldn’t care less what the answers are. However, these are exactly the soils of estimation problems that people in various tech industries have been asking potential employees to evaluate their quantitative reasoning skills. If building physical intuition and evaluating quantitative claims do not seem like sufficient reasons tot you to practice estimation problems, how about the fact that being good at them just might land you a high-paying job? For practice estimating relative lengths, areas, and volumes, check out this PhET (https://openstaxcollege.org/l/21lengthgame) simulation, titled “Estimation.”

Must a complex system be adaptive to be of interest in the field of complexity? Give an example to support your answer.

What are the SI units of ?

Scurrilous con artists have been known to represent gold-plated tungsten ingots as pure gold and sell them to the greedy at prices much below gold value but deservedly far above the cost of tungsten. With what accuracy must you be able to measure the mass of such an ingot in and out of water to tell that it is almost pure tungsten rather than pure gold?

Astronomers want to make maps of the sky showing sources of X-rays or gamma rays. Explain why those X-rays and gamma rays must be observed from above Earth’s atmosphere.

Imagine that a spacecraft has landed on Mercury and is transmitting radio signals to Earth at a wavelength of 10.000 cm. When Mercury is seen from Earth in the evening sky, at its greatest angular distance east of the Sun, it is moving toward Earth at its maximum possible relative speed of 47.9 km/s. To what wavelength must you tune your radio telescope to detect the signals? (Hint: Use the Doppler formula in Reasoning with Numbers 6-2.)

A container of water has a cross-sectional area of A=0.1m2 . A piston sits top of the water (see be following figure). There is a spout located 0.15 m from the bottom of tank, open to the atmosphere, and a stream of water exits the spout. The cross sectional area of the spat is As=7.0104m2 . (a) What is the velocity of the water as it leaves the spout? (b) If the opening of the spout is located 1.5 m above the grand, how far from be pout does water hit the floor? Ignore friction and dissipative forces.

(Indicates a review question, which means it requires only a basic understanding of the material to answer. Questions without this designation typically require integrating or extending the concepts presented thus far.) 27. A ship on a large river approaches a bridge, and the captain notices that the ship is about a foot too tall to fit under the bridge. A crew member suggests pumping water from the river into an empty tank on the ship. Would this help? Why or why not?

Indicates a review question, which means it requires only a basic understanding of the material to answer. Questions without this designation typically require integrating or extending the concepts presented thus far.) Air molecules in a warm room (27°C = 300 K) typically have speeds of about 500 m/s (1,100 mph). Why is it that we are unaware of these fast-moving particles continuously colliding with our bodies?