Question

Which one is not a unit of time?

• A. Leap year
• B. Year
• C. Shake
• D. Light year

Answer 1

Answer: (D)

Light year

Answer 2

Option (a), (b), (c) are unit of time, Shake is an informal unit of time equal to 10 nanosecond or $10^{-8} s$. It has application in nuclear physics. A leap year is a year containing an extra day or month in order to keep the calender year in sync with an astronomical or seasonal year. While light year is the distance that light travels in one year. It is unit of distance and not of time.