Car A and Car B approach each other on the same road. Car A is driving 35.0 m/s, while Car B is driving 15.0 m/s. When Car A honks its horn, Car B hears a frequency of 1140 Hz. What is the frequency of Car A's horn when stationary? (Hint: 1140 Hz is the Doppler-shifted frequency.). (Speed of sound = 343 m/s) (Unit = Hz)

A1000-kg weather rocket is launched straight up. the rocket motor provides a constant acceleration for 16-s, then the motor stops. the rocket altitude 20-s after launch is 510-m. you can ignore any effects of air resistance. a. what was the rocket’s acceleration during the first 16-s? b. what is the rocket’s speed as it passes through a cloud 5100-m above the ground?

Which of the following is the largest disadvantage of about half of the electricity in the united states comes from burning

Only 3% of the water on earth is usable by humans. even though that 3% is through the water cycle, we still need to be careful not to waste water.