QUES: IR data transmission is also employed in short-range communication among computer peripherals and personal digital assistants. These devices usually conform to standards published by IrDA, the Infrared Data Association. Remote controls and IrDA devices use infrared light-emitting diodes (LEDs) to emit infrared radiation that is focused by a plastic lens into a narrow beam. The beam is modulated, i.e. switched on and off, to encode the data. The receiver uses a silicon photodiode to convert the infrared radiation to an electric current. It responds only to the rapidly pulsing signal created by the transmitter, and filters out slowly changing infrared radiation from ambient light. Infrared communications are useful for indoor use in areas of high population density. IR does not penetrate walls and so does not interfere with other devices in adjoining rooms. Infrared is the most common way for remote controls to command appliances. Infrared remote control protocols like RC-5, SIRC, are used to communicate with infrared.
What device is used to transform infrared radiation into an electric current?

ANS: silicon photodiode

QUES: The most common Persian word is Masīhī (مسیحی), from Arabic.,Other words are Nasrānī (نصرانی), from Syriac for "Nazarene", and Tarsā (ترسا), from Middle Persian word Tarsāg, also meaning "Christian", derived from tars, meaning "fear, respect".
Derived from Persian, what does the Arabic Masihi word mean?

ANS: unanswerable

QUES: While LEDs have the advantage over fluorescent lamps that they do not contain mercury, they may contain other hazardous metals such as lead and arsenic. Regarding the toxicity of LEDs when treated as waste, a study published in 2011 stated: "According to federal standards, LEDs are not hazardous except for low-intensity red LEDs, which leached Pb [lead] at levels exceeding regulatory limits (186 mg/L; regulatory limit: 5). However, according to California regulations, excessive levels of copper (up to 3892 mg/kg; limit: 2500), lead (up to 8103 mg/kg; limit: 1000), nickel (up to 4797 mg/kg; limit: 2000), or silver (up to 721 mg/kg; limit: 500) render all except low-intensity yellow LEDs hazardous."
 What LEDs are considered riskier than any other?

ANS: unanswerable

QUES: Northwestern was founded in 1851 by John Evans, for whom the City of Evanston is named, and eight other lawyers, businessmen and Methodist leaders. Its founding purpose was to serve the Northwest Territory, an area that today includes the states of Ohio, Indiana, Illinois, Michigan, Wisconsin and parts of Minnesota. Instruction began in 1855; women were admitted in 1869. Today, the main campus is a 240-acre (97 ha) parcel in Evanston, along the shores of Lake Michigan just 12 miles north of downtown Chicago. The university's law, medical, and professional schools are located on a 25-acre (10 ha) campus in Chicago's Streeterville neighborhood. In 2008, the university opened a campus in Education City, Doha, Qatar with programs in journalism and communication.
When did instruction begin at Northwestern?

ANS:
1855