The SI standard of time is based on:Group of answer choicesYearly revolution of the Earth about the sunA precision pendulum clockVibration of atoms of Cesium-133Frequency of light emitted from Krypton-86Daily rotation of the Earth

The SI standard of length is based on:Group of answer choicesthe distance from the north pole to the equator along a meridian passing through Parisa precision meter stick in Pariswavelength of light emitted by Hg198wavelength of light emitted by Kr86the speed of light

The SI base units for mass, length, and time are:Group of answer choicesgrams, metres, secondsgrams, metres, hoursgrams, kilometres, hourskilograms, metres, seconds,kilograms, metres, hourskilograms, kilometres, hours

A simple pendulum has a time period of  2.0sec at the earth's surface. It is taken to a height  Ro/2 above the earth's surface, where  Ro is the radius of the earth. What is the time period in sec?

An atomic clock moves at 1000 km/h for 1.75 hours as measured by an identical clock on the Earth. At the end of the 1.75 hour interval, how many nanoseconds slow will the moving clock be compared with the Earth-based clock?Hint: The binomial expansion allows the approximationΔtp=1−v2c2−−−−−√Δt≃(1−v22c2)Δt which can be used to find the differenceΔtp−Δt

4. At any given time, how much of Earth isin day and how much is in night?