Question

A seismograph is a scale use for measuring the magnitudes of earthquakes
(a) True
(b) False
(c) Ambiguous
(d) Data insufficient

Answer 1

Hint: A magnitude is a number that shows the power of an earthquake magnitude tells about the size, extant or importance of something.
When the two blocks of the earth suddenly slip past one another, an earthquake occurs. Where they slip, that surface is called the fault or fault plane. From where the earthquake starts located below the earth's surface is known as a hypocenter and directly above the earth’s surface, is called the epicenter.
Sometimes we left aftershocks of an earthquake. These are very less effective. Main shock is the largest main earthquake often aftershocks also occur after the main shocks. If the main shock is strangeness aftershocks can continue for week’s months.

Complete step by step solution:
Cause of an earthquake:
Our earth is made up of four major layers.
$$1.$$The inner care
$$2.$$ Outer care
$$3.$$ Mantle
$$4.$$ Crust
Surface of our planet is made up with the combination of the crust and the top of the mantle. As we can see that the earth surface has a thin skin, but this skiing also made up of many pieces. These pieces keep slowly moving around, sliding past one another and bumping into each other. These pieces are actually in Puzzle form, which are known as tectonic plates and the edges of plates are plate boundaries. These plate boundaries have many faults, where most of the earthquakes occur. Because the edges of the plates are rough, they stick with each other while the other plates keep moving. When the plate has moved enough, the edges unstick on one of the faults and finally there is an earthquake.
Seismograph is also known as a seismometer. It is an instrument used in detecting and recording an earthquake. With the help of seismographs scientists detect earthquakes and measure aspects of the event.

When an earthquake occurs, the epicenter remains just below the earth surface.
The magnitude of an earthquake measured from the logarithm of amplitude of waves recorded seismographs. Actually the Richter scale measures the magnitude of an earthquake.

So (b) is the correct answer that is "false" because a seismograph scale is not used to measure the magnitude of an earthquake.

Note: Don't confuse seismograph and Richter scale. Seismograph is an instrument used to record the data when an earthquake occurs, where Richter scale is used to measure the magnitude of an earthquake.