Ear | MCQs

Explanation

Explanation

Atmosphere is divided into Five layers/parts:

1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere
5. Exosphere

Explanation

A tsunami is a series of powerful sea waves.

It typically caused by underwater earthquakes or volcanic eruptions.

It leading to coastal flooding.

Explanation

• The Earth takes approximately 23 hours, 56 minutes, and 4.9 seconds to complete one rotation on its axis, which is called a sidereal day.
• This is the time it takes for the Earth to rotate once relative to the fixed stars.
• The extra 4 minutes is due to the Earth's slightly ellipsoidal shape and the effects of the Moon's gravitational pull.

Explanation

The stratospheric ozone layer is Earth's “sunscreen”  protecting living things from too much ultraviolet radiation from the sun.

Oxygen layer in the atmosphere

Ozone protects us from the harmful ultraviolet radiation of the sun.

Ozone formula: O3

The ozone layer lies approximately 15-40 kilometers (10-25 miles) above the Earth's surface, in the stratosphere.

The ozone layer is depleting: Air pollution

ND17-7-2023

Explanation

• On Earth, surface water covers 70% area.
• 70-71 percent of the Earth's surface is water-covered.
• The oceans hold about 96.5 percent of all Earth's water.
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• This includes oceans, rivers, lakes, glaciers, and groundwater.
  

Explanation

Priestly discover oxygen in 1776.

Oxygen makes up about 46-50% of the Earth's crust by weight, mainly in the form of oxides and silicates.

It is also a major component of water (H₂O).

It is abundant in the atmosphere as O₂.

Explanation

The moon is a satellite because it moves around Earth.

Earth and the moon are called "natural" satellites.

ND5-07-2023

Explanation

71 percent of the Earth's surface is water-covered, and the oceans hold about 96.5 percent of all Earth's water.

Explanation

A basin is a depression, or dip, in the Earth's surface.

River Drainage Basins.

A river basin is made up of many different watersheds.