SSC
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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second (s)
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minute (min)
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hour (hr)
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year (yr)
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Detailed explanation-1: -The second, symbol s, is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency Cs, the unperturbed ground-state hyperfine transition frequency of the caesium-133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s–1.
Detailed explanation-2: -The SI unit of time is called seconds.
Detailed explanation-3: -Although not an SI unit, the minute is accepted for use with SI units. The SI symbol for minute or minutes is min (without a dot). The prime symbol is also sometimes used informally to denote minutes of time.
Detailed explanation-4: -The basic unit or the S.I. unit of speed is meter per second. This means that to cover a distance of 1 meter, the time required is 1 second.