Tag: structure of earth

Questions Related to structure of earth

The epicenter is the point inside the earth where the earthquake originates

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. True

  2. False

  3. Ambiguous

  4. Data insufficient

Show answer
Correct Option: B
Explanation:

Answer is B.

The point within the earth along the rupturing geological fault where an earthquake originates is called the focus, or hypocenter. The point on the earth's surface directly above the focus is called the epicenter. Earthquake waves begin to radiate out from the focus and subsequently form along the fault rupture. 
Hence, the statement is false.

Earthquake and tsunamis are difficult to predict

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Answer is A.

Earthquakes are caused by by shaking of the earth, strain building up in the tectonic plates, plates slipping along the fault lines, etc. and the Tsunamis can also be caused by volcanic eruptions, underwater detonations and even landslides.
Because we cant get deep enough into the Earth to see what happens before an earthquake or tsunami happens, therefore we cant predict when its coming.

A seismograph is a scale use for measuring the magnitudes of earthquakes

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. True

  2. False

  3. Ambiguous

  4. Data insufficient

Show answer
Correct Option: B
Explanation:

Answer is B.

Seismograph is an instrument that makes a record of seismic waves caused by an earthquake, explosion, or other Earth-shaking phenomenon. Seismographs are equipped with electromagnetic sensors that translate ground motions into electrical changes, which are processed and recorded by the instruments analog or digital circuits. A record produced by a seismograph on a display screen or paper printout is called a seismogram.
Hence, it is not a scale and the statement is false.

The term used to describe a fracture along the earth's crust is

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. aftershock

  2. fault

  3. focus

  4. tremor

Show answer
Correct Option: B
Explanation:

Answer is B.

The fracture along blocks of crust (tectonic plates) is called a fault or fault line.
A fault is a planar fracture or discontinuity in a volume of rock, across which there has been significant displacement along the fractures as a result of earth movement. Large faults within the Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes.

Choose the correct statement.

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. 'P' waves are slower than 'S' waves.

  2. Both 'P' and 'S' waves have same speed.

  3. 'S' waves are slower than 'P' waves.

  4. None of the above.

Show answer
Correct Option: C
Explanation:
The P waves and the S waves are the waves that travel throughout the planet. The P waves are the compression waves that apply force in the direction of propagation whereas the S waves are shear waves that make the medium particle move perpendicular to their direction of motion.
The energy is less easily transmitted in the medium in the case of S waves. So, P waves travel faster.

Option $C$ is correct.

How do we record seismic waves?

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. With the help of a seismogram.

  2. With the help of a seismograph.

  3. With the help of a seismocity.

  4. None of the above.

Show answer
Correct Option: B
Explanation:

Seismograph is a device which is used to record and measure seismic waves created by earthquakes.

A seismograph is also known as:

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. seismogram

  2. seismology

  3. seismometer

  4. seismocity

Show answer
Correct Option: C
Explanation:
A seismograph, which measures seismic waves, is also known as a seismometer.

'S' waves are

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. Longitudinal

  2. Electromagnetic

  3. Ultrasonic

  4. Transverse

Show answer
Correct Option: D
Explanation:

The S waves moving through the planet make the medium to move perpendicular to the direction of the propagation of the wave. Therefore. the S waves are regarded as the transverse waves.

Waves produced due to earthquakes are known as :

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. seismic waves

  2. shock waves

  3. infrasonic waves

  4. destructive waves

Show answer
Correct Option: A

Waves produced due to the earthquake are known as

physics structure of earth seismic waves and tsunami causes of earthquakes origin of earth and its internal energy transfer of charge lightning safety

  1. seismic waves

  2. shock waves

  3. infrasonic waves

  4. Tectonic waves

Show answer
Correct Option: A