Two different balls are rolled (without slipping) toward a common finish line. Ball 1 has an angular speed of 1=21.2 rad/s, and ball 2 has an angular speed of 2=16.8 rad/s. The first ball, which has a radius of 0.0588 m, is rolling along a conveyor belt that is moving at 1.19 m/s and starts out 8.72 m from the finish line. The second ball has a radius of 0.0488 m and is rolling along the stationary floor. Two balls are vertically offset and are rolling with clockwise angular speed towards a vertical finish line to the right. Ball 1 rolls with an angular speed of omega subscript 1 on a conveyor belt above ball 2. Arrows indicate that the top surface of the conveyor belt that ball 1 is on moves to the right, while the bottom surface of the conveyor belt moves to the left. Ball 2 rolls with an angular speed of omega subscript 2 on a stationary floor. If the second ball starts out 6.59 m from the finish line, how long does each ball take to reach the finish line? ball 1: s ball 2: s What angular speed would the losing ball have needed to cross the finish line at the same time as the winning ball?

19. explain why a magnet from your refrigerator could not be used to lift something as heavy as a car. (chapter 7 – pages 202-203) 20. can a magnet ever have a single pole? explain your answer. (chapter 7 – page 208) 21. what happens to the wavelength of a wave if the frequency is increased? (chapter 9 – pages 280-281) 22. an ocean wave has a wavelength of 10 m and a frequency of 4.0 hz. what is the velocity of the wave? show the appropriate equation from your book and show your work with units. (chapter 9 – page 282) 23. as you sit outside, the sound of a siren becomes lower in pitch. is the emergency vehicle moving away from or towards you? explain how you know. (chapter 10 – page 315-316) 24. why are two astronauts in space unable to hear one another? (chapter 10 – page 307) 25. explain in at least 3 sentences how electromagnetic waves form. (chapter 11 – page 338-339) 26. using the chart on page 345 in your textbook, what are the three types of electromagnetic wave with wavelengths shorter than those of visible light. give an example of each. (chapter 11 – pages 345-351) 27. explain why a leaf usually appears to be green, but a rose typically appears red. (chapter 12 – page 373) 28. what is the difference in light that is refracted compared to light that is reflected? think in terms of speed of light as well as what happens to light waves when they interact with a medium. (chapter 12 – pages 369-370) 29. how are concave and convex lenses different? (chapter 13 – page 408-410) 30. what type of mirror is used in rearview mirrors in cars? why is it important that these mirrors have the warning, “objects in mirror are closer than they appear.”? (chapter 13 – page 405)

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !

The friction of the water on a boat produces an acceleration of -10. m/s2. if the boat is traveling at 30. m/s and the motor is shut off, how long it take the boat to slow down to 5.0 m/s?