SCIENCE
PHYSICAL SCIENCES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Seconds
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Hours
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Days
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None of the above
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Detailed explanation-1: -The second (s or sec) is the International System of Units (SI) unit of time measurement. One second is the time that elapses during 9, 192, 631, 770 (or 9.192631770 x 109 in decimal form) cycles of the radiation produced by the transition between two levels of the cesium-133 atom.
Detailed explanation-2: -We measure time in seconds, minutes, hours, days, weeks, months and years with clocks and calendars. A day has 24 hours. We use A.M. to tell the time running from midnight to noon and P.M. for the time running from noon to midnight.
Detailed explanation-3: -Seconds were once derived by dividing astronomical events into smaller parts, with the International System of Units (SI) at one time defining the second as a fraction of the mean solar day and later relating it to the tropical year.
Detailed explanation-4: -Clock is basic time measuring device, it works on the principle of periodic motion. Clock are of different types table clock, digital clock, wall clock etc.