Seismograph is an instrument that records the :
vibrations of the surface of earth
duration of a solar eclipse
intensity of a thunderstorm
heights of tides
Seismograph is an instrument that records the vibrations of the surface of earth.
The duration of a lunar eclipse is longer than a solar eclipse.
When the Moon comes in between the Sun and the Earth in a straight line, then a solar eclipse is formed. This formation of a solar eclipse is based on the concept of: