« previous next »

Author Question: A policeman in a stationary car measures the speed of approaching cars by means of an ultrasonic ... (Read 82 times)

future617RT

  • Hero Member
  • *****
  • Posts: 543
on: Jul 29, 2018
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

Question 2

A steel sphere with a radius of 2.0 m falls off a ship and sinks to a depth where the pressure is 15 MN/m2. The bulk modulus for steel is 1.61011 N/m2. What is the change in the radius of the sphere?
 
  A)
 
  0.021 mm
 
  B)
 
  4.2 mm
 
  C)
 
  0.42 mm
 
  D)
 
  0.19 mm
 
  E)
 
  0.063 mm


Bsand8

  • Sr. Member
  • ****
  • Posts: 327
Reply #1 on: Jul 29, 2018
Answer to Question 1

A

Answer to Question 2

E


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Hip fractures are the most serious consequences of osteoporosis. The incidence of hip fractures increases with each decade among patients in their 60s to patients in their 90s for both women and men of all populations. Men and women older than 80 years of age show the highest incidence of hip fractures.

Did you know?

Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.

Did you know?

Atropine was named after the Greek goddess Atropos, the oldest and ugliest of the three sisters known as the Fates, who controlled the destiny of men.

Did you know?

During pregnancy, a woman is more likely to experience bleeding gums and nosebleeds caused by hormonal changes that increase blood flow to the mouth and nose.

Did you know?

When taking monoamine oxidase inhibitors, people should avoid a variety of foods, which include alcoholic beverages, bean curd, broad (fava) bean pods, cheese, fish, ginseng, protein extracts, meat, sauerkraut, shrimp paste, soups, and yeast.

Use of an Ultrasonic Stethoscope to Detect a Dorsalis Pedis Pulse Use of an Ultrasonic Stethoscope to Detect a Dorsalis Pedis Pulse
Localization of a Peptide The peptide is revealed by means of immunocytochemistry. The photomicrogra Localization of a Peptide The peptide is revealed by means of immunocytochemistry. The photomicrogra
Top Eleven Countries in Year 2009 According to Three Different Measures Top Eleven Countries in Year 2009 According to Three Different Measures
Speed of Light in Different Mediums Speed of Light in Different Mediums
A pool player is attempting a fancy shot. He hits the cue ball giving it a speed of 5.57 m/s ... A pool player is attempting a fancy shot. He hits the cue ball giving it a speed of 5.57 m/s ...
A concrete wall of a cold storage room measures 3.0 m high, 5.0 m wide, and 20 cm thick. The ... A concrete wall of a cold storage room measures 3.0 m high, 5.0 m wide, and 20 cm thick. The ...
Video: Otitis Media

For a complete list of videos, visit our video library