An Automobile Traveling at 45 Mi/h (= 20

question 19

Multiple Choice

An automobile traveling at 45 mi/h (= 20.0 m/s) blows a horn at a constant 600 Hz.What is the frequency observed by a stationary observer as the car approaches?

• A)512 Hz
• B)567 Hz
• C)600 Hz
• D)612 Hz
• E)638 Hz

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Definitions:

Hydraulic Power Brake Booster

A device that uses hydraulic pressure to assist in the application of the vehicle's brakes, reducing the effort required by the driver.

Hydraulic Assist

An external power brake assist system that uses hydraulics, typically from the power steering system to a hydraulic power brake booster.

Lateral Acceleration Sensor

A device in a vehicle that measures the sideways acceleration to help with stability control and other functions.

Slip Rate

A term used to describe the rate at which one surface slides over another, commonly referenced in automotive and mechanical engineering contexts.