Which of the following best describes a seismograph?

• A. A tool for measuring electric current in a circuit.
• B. An apparatus for determining the density of a liquid.
• C. An instrument that measures and records the vibrations of the ground during an earthquake.
• D. A device used to measure atmospheric pressure.

Answer: (C)

Verified step by step guidance

1. Understand the purpose of a seismograph: it is designed to detect and record vibrations or seismic waves generated by earthquakes or other ground movements.
2. Recall that seismic waves cause the ground to shake, and the seismograph translates these ground motions into a visual record called a seismogram.
3. Recognize that the seismograph consists of a mass suspended on a frame that moves relative to the ground, allowing it to detect vibrations accurately.
4. Compare the options given: measuring electric current relates to ammeters or voltmeters, determining liquid density involves hydrometers or densitometers, and measuring atmospheric pressure uses barometers.
5. Conclude that the correct description of a seismograph is 'an instrument that measures and records the vibrations of the ground during an earthquake.'