Very Short Answer Type Question
Question. Why there is a dense fog near Newfoundland?
Answer : Near the Islands of Newfoundland the warm water of Gulf Stream mixes with the cold water of Labrador. Due to this a dense fog is formed over there.
Question. Write down the main ocean currents of North Atlantic Ocean cycle.
Answer : 1. The Gulf Stream
2. Canary Current
3. Saragasso Sea
Short Answer Type Question
Question. Why are the ocean currents of Indian Ocean not so definite and systematic?
Answer : The winds in the Indian Ocean are seasonal and change their direction. Due to this, the ocean currents also change their direction. This is the reason the ocean currents of Indian Ocean are not so definite and systematic.
Question. Why a Spring Tide occurs in full moon and no moon days?
Answer : The sun, the moon and the earth all are in a line during no moon day and full moon day. This is the reason, a spring tide occurs in both these phases.
Question. What is the difference between the ocean waves and the ocean currents?
Answer :
Ocean Waves
The waves arise due to the speed of the wind blowing over the surface of oceans. The water of the oceans always ripples with the winds over the Ocean surface. These are called waves.
Ocean Currents
When the ocean water moves in a particular direction it is called ocean current. The water in the ocean keeps on moving from one place to the other.
I. FILL IN THE BLANKS.
1. The major sources of ____________________are the rivers, ponds, springs and glaciers.
2. ______________________in Israel has a salinity of 340grams per litre of water.
3. The __________________ in Andaman and Nicobar Island got submerged after tsunami.
4. Tsunamis are rare in__________________ as the seismic activities are less as compared to the Pacific Ocean
5. The first indication that tsunami is approaching is the rapid ___________________of water from the coastal region.
6. During full moon and new moon days the tides occur are called_______________________
7. When the moon is in first and last quarter ,the low tides occur are called_________________________
8. ____________________tides help in navigation, fishing and generating electricity.
II. NAME THE FOLLOWING:
1. The artificial enclosure for keeping small plants____________________
2. The world water day is celebrated on _____________________
3. The term tsunami originated from the Japanese word _________________
4. The rhythmic rise and fall of ocean water twice a day_____________________
5. An example for cold current_____________________
III. MATCH THE FOLLOWING
COLUMN ‘A’ COLUMN ‘B’ RESPONSE
1. Caspian sea a. December 2004 1.
2. Tsunami in Indian Ocean b. Largest lake 2.
3. Neap tides c. High tide 3.
4. Gulf stream d. Equator 4.
5. Spring tides e. Gravitational pull 5.
6. Warm ocean currents f. Warm current 6.
7. Tides g. Low tides 7.
IV. ANSWER THE FOLLOWING IN TWO POINTS.
1. How can we measure salinity of water?
2. How Dead Sea of Israel differ from other water bodies?
3. What are waves?
4. What are spring tides and neap tides?
V ANSWER THE FOLLOWING IN THREE POINTS
1. What are tides?
2. What are the advantages of tides?
3. What are the advantages of ocean currents?
VI ANSWER THE FOLLOWING IN FOUR POINTS
1. Write a short note on Tsunami.
2. Explain ocean currents.
3. Why so many countries face water scarcity?
VII IN THE GIVEN OUTLINE MAP MARK THE FOLLOWING OCEAN CURRENTS (COLD CURRENTS WITH BLUE AND WARM CURRENTS WITH RED)
EXTRA NOTE:OBSERVE THE DIAGRAM AND LEARN THE FACTS ABOUT TIDES
Please click on below link to download CBSE Class 7 Social Science Water Worksheet Set B
