A Policeman in a Stationary Car Measures the Speed of Approaching

question 52

Multiple Choice

A policeman in a stationary car measures the speed of approaching cars by means of an ultrasonic device that emits a sound with a frequency of 41.2 kHz. A car is approaching him at a speed of 33.0 m/s. The wave is reflected by the car and interferes with the emitted sound producing beats. What is the frequency of the beats? The speed of sound in air is 330 m/s.

• A) 9.2 kHz
• B) 4.1 kHz
• C) 4.6 kHz
• D) 1.2 kHz
• E) 8.2 kHz

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Definitions:

Lease Liability

An obligation representing future lease payments a lessee is required to make under a lease agreement.

Discount Rate

The discount rate applied in calculating the present value of future cash flows during discounted cash flow analysis.

Lessor's Income Recognition

The process by which lessors report income earned from leasing out assets, typically recognized over the lease term.

Operating Lease

A lease arrangement in which the lessee has the right to use an asset for a short portion of its useful life, and the lease does not meet the criteria to be recognized as a capital lease.