Exercises
1. Answer the following questions.
(1) What is precipitation?
(11) What is water cycle?
(11) What are the factors affecting the height of the waves?
(iv) Which factors affect the movement of ocean water?
(v) What are tides and how are they caused?
(vi) What are ocean currents?
Answers
(i) - Precipitation: Precipitation is any form of liquid or solid water particles that fall from the atmosphere and reach the surface of Earth. This may be in the form of rain, hail, frost, fog, sleet or snow.
(ii) - Water Cycle: The process by which water continually changes its form and circulates between oceans, atmosphere and land is known as the water cycle.
(iii) - The factors affecting the height of waves are:
a-The high speed of the wind.
b-Pushing action of winds blowing over the ocean.
c-Duration of wind.
d-The distance the wind blows on water
Earthquake.
d-Volcanic Eruption.
e-Underwater Landslides.
(iv) - The factors affecting the movement of ocean water are:
a-Earth’s rotation
b-Salinity
c-Prevailing winds
d-Variation in Temperature
e-The gravitational pull of sun and moon
Earthquakes and volcano.
(v) - Tides: The rhythmic and alternate, rise and fall of ocean water twice a day is called a tide.
a-Tides are caused due to the gravitational pull exerted by the sun and the moon on the earth’s surface.
b-The moon is closer to the Earth is responsible for tides to a greater extent than the Sun.
c-When the level of the Water is highest, it is called High Tide.
d-When the level of water is the lowest, it is called Low Tide.
(vi)-Ocean currents: Large Scale movement of water in the oceans in a definite direction are called ocean currents. The ocean currents are like rivers in the ocean that are of thousands of kilometers in length and very wide also. The ocean currents are of two types. That are- Warm Currents and Cold Currents. For example, the Labrador ocean current is cold current and the Gulf Stream is warm current.
ANSWER:
i. Falling of moisture in the form of rainfall, snow, fog, sleet and hailstone is termed os precipitation.
ii. The water cycle is the process by which water continually change it forms and circulates between oceans, atmosphere and land.
iii. wind, earthquakes, volcanic eruption or underwater landsides are the factor affecting the height of the wave. The stronger the wind blows, the bigger the wave come.
iv. Temperature, wind, the gravitational pull of the sun, the Earth and the Moon ; warm and cold currents are the factors that affect the movement of ocean water.
v. tides are the rhythmic rise and fall of ocean water that occur twice in a day. The strong gravitational force pull exerted by the sun and the moon on the earth surface cause the tides.
vi. Ocean currents are streams of water flowing constanly on the ocean surface in definite direction.