The speed of sound at sea level is normally about 340 m/s. An ambulance has a siren with a frequency of 10,000 Hz. After it passes an observer, the observer records a frequency of 9,500 Hz. What is the velocity of the ambulance?

Aball tossed vertically upward from the ground next to a building passes the bottom of a window 1.8 s after being tossed and passes the top of the window 0.20 s later. the window is 2.0 m high from top to bottom. what was the ball's initial velocity? the unit vector j^ is directed upward. how far is the bottom of the window from the launch position? how high does the ball rise above the launch position?

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer

Cathy is pedaling down a steep hill on her bicycle and wants to be able to coast up the next hill, which is 25 meters high, without pedaling. cathy and her bicycle have a mass of 75 kg. assuming her bicycle is 100% efficient, what would her speed have to be?