what is the difference between a police siren?
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In the US, fire departments, ambulances and police departments all buy their electronic sirens from the same manufacturers. Other than the slight difference from being mounted on different sized vehicles, there is no real difference in sound.
565035
Wave usually refers to a continuous disturbance. Like if you grab hold of spring and shake it back and forth a lot. Pulse, on the other hand, often refers to some type of one-time disturbance. Like shaking the spring only once.
787854
D. There essentially are two ways to police: reactive and proactive. Reactive policing is epitomized by officers responding to calls-for-service. Proactive policing is getting out in front of events in the hopes of preventing crimes and working with the community to reduce crimes.
1440056
Almost all sirens in the emergency vehicles are made by the federal signal corporation or Motorola. ... Ambulances generally have the same type of siren but they're louder because the speaker is usually on the outside of the ambulance.
1106335
Police can control traffic lights with Opticom Traffic Preemption. ... Sound echoes could cause the green to go to the wrong traffic. The use of infrared (IR) light has become more popular than the siren based system. A strobe mounted with the standard police lights sends out an IR signal to turn traffic lights green.
730067
A pulse refers to a disturbance that travel from one location to another location through a medium. While, A wave refers to the disturbance or variation that travels through the medium.
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"Gunshots are very crisp and they have a certain timing or cadence to them." "Fireworks are very loud, just like gunfire, but they are very sporadic. There is a lot of crackling, sometimes they echo and sometimes there is a whistle before the fireworks. You can see that it sounds kind of similar.
608136
The difference between BLS and CPR is that the BLS class is an advanced CPR AED course. BLS is an abbreviation for Basic Life Support. The BLS CPR AED is a healthcare level CPR. ... If you are not a medical/healthcare professional the best course for you would be a standard CPR AED course with or without First aid.
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BMW anti-theft alarm system. The anti-theft alarm system protects the vehicle against unauthorised access by activating the hazard lights and setting off an acoustic alarm. ... Comprising a control unit (with back-up battery), siren, ultrasonic or microwave sensors (depending on vehicle), cable set and mounting parts.
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The main difference between stationary and moving mode radar is moving radar also measures patrol vehicle speed by measuring the ground reflection speed. A moving radar measures traffic speed relative to the radar, closing speed for on-coming traffic.
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Code 1: A time critical case with a lights and sirens ambulance response. An example is a cardiac arrest or serious traffic accident. Code 2: An acute but non-time critical response.
740653
Since the 1990s, civil defense sirens have been replaced by electronic sirens, and the procedure has been simplified. As of 2013, there are four playable tones: a natural disaster warning, an upcoming air/nuclear strike, an imminent air/nuclear strike, and an 'all clear' signal.
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The major difference between the two is the conveying of information. A signal is always talked about in terms of conveying some information about some phenomenon. ... A wave can be considered a part of a signal, like a 1 MHz sinusoidal signal will have a million sine waves per second.
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A one way alarm system only lets you send a signal to the vehicle. A two way system lets you send a signal to the vehicle and it also allows the vehicle to send one back to you.
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In an emergency situation, drivers of emergency vehicles are granted certain exemptions to the law while using their sirens and blue lights. In these circumstances, an emergency vehicle can do the following things: Disobey the speed limit (if it's a police car, ambulance or fire engine).
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There are a number of differences between a smoke detector and a fire alarm system. ... A smoke detector simply acts as a sensor and detects the smoke while a fire alarm system acts on it. A fire alarm system has a number of different devices all joined together to give your building protection from fire.
1267049
In addition to its "voice" feature, which acts as a loudspeaker, the LRAD has an "alert" feature, which emits loud chirping sounds that have been reported to cause pain and hearing damage. The LRAD is often considered to be a sonic weapon. The NYPD's LRAD use is being challenged in federal court.