Answer: Option [A]Instrument used to measure earthquake is known as seismograph. Seismographs are instruments used to record the motion of the ground during an earthquake. They are installed in the ground throughout the world and operated as part of a seismographic network. The earliest "seismoscope" was invented by the Chinese philosopher Chang Heng in A.D. 132.
Answer: Option [C]The correct answer is Richter scale. The measurement scale developed by Charles Francis Richter that is used to measure the strength of an earthquake is called the Richter Scale.
Answer: Option [D]The point within the Earth where earthquakes originate is focus. The point where an earthquake originates is called the seismic focus. It is also known as hypocenter.
Answer: Option [C]The correct answer is epicenter. The point on the Earth's surface directly above the focus is the epicenter. When energy is released at the focus, seismic waves travel outward from that point in all directions.
Answer: Option [C]In general, the most destructive earthquake waves are the Surface waves. By a property called dispersion, surface waves of different wave lengths travel at different velocities. It is the surface waves which cause most property damage because surface waves produce more ground movement and travel more slowly, so they take longer to pass.
