Question

The Japanese terms 'tsu' and 'nami' in the word 'Tsunami' mean
1. total destruction
2. giant wave
3. harbour wave
4. violent wave

Answer 1

Correct Answer - Option 3 : harbour wave

The correct answer is harbour wave.

• In Japanese, 'Tsu' means Harbour and 'nami' means wave.
• A tsunami is a series of waves in a large water body viz. Ocean or Sea caused by the displacement of large volume of water.
• It happens when Earthquake or Volcanic eruptions occur underwater.
• The speed of a wave in the ocean depends on the depth of water. Speed is more in shallow water which is why the coast has more impact as compared to the ocean.

•  Earthquake occurs because of sudden movements in the Earth's crust or upper mantle.
• It is measured by a device called a seismograph which measures the magnitude of the Earthquake.
• Causes-
  1. Fault Zones - sudden slipping of rocks and rupturing of rocks.
  2. Plate Tectonics - Movement of plates along the faultlines.
     • Divergent - Plates moving away from each other
     • Convergent - Plates colliding with each other
     • Transform - plates sliding past each other
  3. Volcanic Activity
  4. Human activities
• Earthquake waves - 
  • Primary wave - Fastest and travels in solid and liquid i.e. Crust, Magma and Core.
  • Secondary wave - Travels only through solid i.e. Crust.
  • Surface wave - Move along the surface, causes maximum destruction.