An ambulance driving 50.0 m/s emits a sound wave with a length of 80.0 centimeters. As it drives towards a hospital, which of the following is the only possible frequency heard by the medical staff who are standing at the entrance? Speed of sound is 343 m/s.

A. 62.5 Hz
B. 73.2 Hz
C. 429 Hz
D. 502 Hz

Is the number of complete movements of a wave per second.

If a car is traveling on the highway at a constant velocity, the force that pushes the car forward must be a. equal to the weight of the car. b. less than the force of friction exerted upon the car. c. equal to the force of friction exerted upon the car. d. greater than the weight of the car.

Pl i beg u so much now propane burns in oxygen to produce carbon dioxide and steam. the unbalanced equation for this reaction is: c3h8 + o2 → co2 + h2o use coefficients to balance this equation. a) c3h8 + 3 o2 → 3 co2 + 4 h2o b) c3h8 + o2 → 3 co2 + 4 h2o c) c3h8 + 5 o2 → 3 co2 + 4 h2o d) 2 c3h8 + 5 o2 → 3 co2 + 4 h2o