Maharashtra Board Class 7 Science Chapter 10 Disaster Management Solutions

Question 1. Find the odd man out:

Question a.
Famine, earthquake, cloudburst, railway accident.
Answer:
Railway accident.
In simple words: Railway accident is a man-made disaster, while famine, earthquake, and cloudburst are natural disasters.

🎯 Exam Tip: Identifying the type of disaster (natural vs. man-made) is key to solving odd-man-out questions effectively.

Question b.
Drought, heavy rains/storm, tsunami.
Answer:
Drought.
In simple words: Drought represents a lack of water, while heavy rains, storms, and tsunamis involve an abundance or powerful movement of water.

🎯 Exam Tip: Focus on the common characteristic shared by most options and find the one that deviates.

Question c.
Lava, hot mud, ash, locusts.
Answer:
Locusts.
In simple words: Lava, hot mud, and ash are all associated with volcanic eruptions, whereas locusts are an insect pest causing agricultural damage.

🎯 Exam Tip: Grouping related phenomena (e.g., volcanic materials) helps distinguish the unrelated item.

Question d.
Washing away of crops, attack of pests on crops, volcano, singeing of crops.
Answer:
Volcano.
In simple words: Washing away of crops, attack of pests, and singeing of crops are all phenomena related to agricultural damage, while a volcano is a geological event.

🎯 Exam Tip: Understand the primary impact or source of each event to categorize and find the outlier.

Question 2. What are the remedial measures for the following calamities?

Question a.
Famine:
Answer:
Following are the remedial measures for famine:
1. Supply food and water to the people those who are dying due to hunger.
2. Give medicines to the people those who are suffering from malnutrition.
3. Government should start helping centres for the people those who are suffering from famine.
4. Give them temporary shelter in some other places where water and food are available.
5. Shift the animals to safer places.
6. Do proper planning so that region doesn't get famine again and again.
7. Reuse water
8. grow more trees.
In simple words: Remedial measures for famine primarily involve providing immediate relief like food, water, and shelter, along with long-term strategies such as proper planning, water reuse, and afforestation to prevent recurrence.

🎯 Exam Tip: When listing remedial measures, categorize them into immediate relief, public health, and long-term prevention for a comprehensive answer.

Question b.
Lightning strike:
Answer:
Following are the remedial measures for lightning strike:
1. Give immediate treatment to the lightning affected persons so their life can be saved.
2. Keep the people away from the open ground and swimming pool.
3. Provide them proper guidelines to cure for the lightning strike.
In simple words: For lightning strikes, the remedies involve immediate medical aid for victims, ensuring people avoid exposed areas during a storm, and educating the public on safety guidelines.

🎯 Exam Tip: Focus on both emergency response and preventive actions when discussing measures for natural calamities.

Question c.
Storm:
Answer:
1. Supply food, water and medicines to the people
2. Shift them to safe places.
3. Maintain peace, and advice the people not to panic.
4. Give time to time report on T.V. and radio.
In simple words: Remedial measures for a storm include providing essential supplies, evacuating people to safety, managing public panic, and disseminating timely information through media.

🎯 Exam Tip: Emphasize communication and logistical support as crucial elements in storm disaster management.

Question d.
Cloudburst:
Answer:
Following are the remedial measures for cloudburst:
1. Shift people to safe places with the help of airplane, helicopter and army.
2. Supply them food, clothes, water and medicines.
3. Give time to time weather report.
4. Open more helpline centres.
5. Government should immediately send the help in terms of money and army to the people.
In simple words: For cloudbursts, immediate actions involve evacuating affected populations using specialized transport, providing essential relief materials, issuing continuous weather updates, establishing helplines, and deploying government aid and military support.

🎯 Exam Tip: Highlight the urgency and multi-agency coordination required for effective cloudburst response.

Question 3. True or false? Give reasons for your answer.

Question a.
Information about a forthcoming storm is to be kept secret.
Answer:
False. Information about a forthcoming storm is not to be kept secret because, with this information we can take immediate steps for disaster management. Large scale damage of property and loss of life can be avoided.
In simple words: It is false to keep storm information secret; early public warnings are crucial for taking timely precautions, minimizing damage, and saving lives.

🎯 Exam Tip: Always emphasize transparency and early warning systems as fundamental principles of effective disaster management.

Question b.
You should not swim when there is lightning in the sky.
Answer:
True. Lightning carries some electric charges which causes electric current in it. Water catches this current so if any person is swimming pool during lightning in the sky, then there are more chances that lightning may strike in water and the person may die due to it.
In simple words: This statement is true because water conducts electricity, making it extremely dangerous to be in a swimming pool or any open water during a lightning storm, as strikes can electrify the water.

🎯 Exam Tip: Connect the physical properties (water as a conductor) to the safety advice for a strong reasoning argument.

Question c.
It is possible to prevent the eruption of a volcano.
Answer:
False. It is not possible to prevent the eruption of a volcano because it is a natural event. However, by means of science and technology, it is possible to predict an eruption in advance and to take immediate steps for disaster management.
In simple words: It is false that volcanic eruptions can be prevented, as they are natural geological processes; however, science allows us to predict them and take preparatory disaster management steps.

🎯 Exam Tip: Differentiate between preventing a natural phenomenon and mitigating its effects through prediction and preparation.

Question d.
Heavy rains result in famine.
Answer:
True. Heavy rains result in flood so crops get washed away or damaged in the flood and results in famine.
In simple words: This is true because heavy rains cause floods that destroy crops, leading to food scarcity and eventually famine.

🎯 Exam Tip: Understand the chain of events: heavy rains -> floods -> crop damage -> food shortage -> famine.

Question e.
A loud crashing sound follows a lightning.
Answer:
True, Friction and brushing happens between two clouds making them charged and lightning is produced between two clouds or one cloud and earth. The temperature increases and air pressure also increases to high amount and produces a loud sound of thunder.
In simple words: This is true; the intense heat from a lightning discharge rapidly expands the surrounding air, creating a shockwave that we hear as the loud crashing sound of thunder.

🎯 Exam Tip: Explain the physical process (rapid air expansion due to heat) behind the sound of thunder.

Question 4. Write answers to the following questions in our own words.

Question a.
What is a tsunami? What gives rise to a tsunami?
Answer:
1. Waves generated by an earthquake or volcano occurring on the ocean floor is called 'tsunami'. 'Tsunami' is a Japanese word which means 'harbour wave'.
2. As on land, earthquakes and volcanic eruptions occur, at the bottom of the sea, too.
3. If an earthquake occurs at the bottom of ocean, the energy released pushes the water upwards. As a result of this particular type of waves are formed.
4. These waves are not very high near the source, but they start spreading very fast to long distances.
5. The velocity of these waves is 800 to 900 km/hr. When they reach a coastal area, their velocity is reduced, but their height is found to have increased tremendously even to about 30 m. These are tsunami waves.
In simple words: A tsunami is a series of powerful ocean waves primarily caused by large-scale underwater disturbances, like earthquakes or volcanic eruptions on the seafloor, which displace a massive volume of water. These waves travel rapidly across the ocean and grow significantly in height as they approach coastal areas.

🎯 Exam Tip: Define "tsunami" and clearly explain its primary causes and how its characteristics (speed, height) change as it approaches the coast.

Question b.
What is cloudburst?
Answer:
1. Sometimes the water coming down from rain clouds does not reach the land in the form of rain. Instead, due to very high temperature near the land, it vaporizes and goes back into the same clouds.
2. As a result the amount of vapour in those clouds becomes very high.
3. Due to rapid condensation, it rains suddenly over a specific and small region at a rate of 100 mm per hour or more. This is known as a cloudburst.
In simple words: A cloudburst is a sudden, extreme rainfall event, where a very large amount of rain, at least 100 mm per hour, falls rapidly over a small geographical area, often due to moisture-laden clouds that accumulate excessive vapor and then condense quickly.

🎯 Exam Tip: Include the specific rainfall rate (100 mm/hour) and the localized nature of a cloudburst in your explanation.

Question c.
Explain the effects of a volcano.
Answer:
Following are the effects of a volcano:
1. The chemical substances such as lava, vapour, hot mud, sulphur etc. get collected on the surface of the earth and thereby mountains and hills are created
2. The atmosphere gets polluted due to the ash and gases ejected by the volcano.
3. Often, it rains as a result of a volcanic eruption.
4. The temperature rises due to hot gases.
5. Forests and settlement get buried under the hot mud.
In simple words: Volcanic eruptions cause significant environmental and geological changes, including the formation of new landforms, severe atmospheric pollution from ash and gases, localized temperature increases, and destructive burial of ecosystems and settlements under lava and mudflows.

🎯 Exam Tip: Cover a range of effects-geological, atmospheric, and ecological-for a comprehensive answer on volcanoes.

Question d.
What are the measures to prevent loss of life due to lightning?
Answer:
Following are the measures to prevent loss of life due to lightning:
1. Do not stand on open ground, below a tree, on high location, near an electric pole, near a telephone pole or a tower etc.
2. Do not lean on wire fences around a farm, a compound, a garden or a house.
3. If you are on two-wheeler, a bicycle, a tractor or a boat, get off immediately and go to safe place.
4. Do not gather all together in one place.
5. Take care to keep a distance of 15 feet between any two persons.
6. Do not use plugged in electrical appliances. Do not use a mobile or telephone.
7. Stand on dry wood, a plastic sheet, sack or jute cloth or dry leaves.
8. Keeping your feet together support yourself on the soles of your feet placing your hands on your knees and crouch low.
9. Swimmers and fishermen should immediately come out of the water.
10. A pucca house is the safest place. Find out if there is a lightning conductor on any tall building near your house. If necessary get a lightning conductor fitted on your house.
In simple words: To prevent lightning fatalities, one should avoid open spaces, tall objects, and conductive materials, seek shelter indoors, avoid electrical gadgets, and if outdoors without shelter, adopt a low crouch position on an insulating material.

🎯 Exam Tip: Provide a mix of "what not to do" and "what to do" actions for a well-rounded answer on lightning safety.

Question 5. What measures have been taken to deal with calamities such as floods and landslides under the disaster management programme in Maharashtra?

Question a.
What measures have been taken to deal with calamities such as floods and landslides under the disaster management programme in Maharashtra?
Answer:
In Maharashtra, all districts have their own disaster management plan to deal with calamities such as floods and landslides.
1. The plan deals extensively with the emergency, and evacuation measures to be taken up in cases of flood and landslide.
2. The district-level disaster management plan has detailed information about geographical details, population, flood-prone areas, villages and other macro details.
3. Nearly 14 such key departments are engaged in disaster mitigation measures and each one has been assigned a specific task to do at times of natural disasters.
4. The administration is now training master trainers at the district level who in turn will train key persons at village and taluka levels to deal with a natural disaster.
5. The administration through radio jingles, public advertisements and other measures is informing people about how to react at times of flood and landslide.
6. Currently, the Indian Meteorological Department (IMD) gives weather forecast on daily basis and for the next 5 days with advice to farmers on when to start crop sowing and harvesting etc.
In simple words: Maharashtra's disaster management plan for floods and landslides involves district-specific plans detailing emergency response and evacuation, comprehensive data on vulnerable areas, engagement of multiple departments with assigned tasks, training of personnel from district to village levels, public awareness campaigns, and daily weather forecasts from IMD for preparedness.

🎯 Exam Tip: Highlight the multi-faceted approach of disaster management, covering planning, training, public awareness, and meteorological support.

Question 6. With reference to disaster management what are the things in your house that you will check?

Question a.
With reference to disaster management what are the things in your house that you will check?
Answer:
With reference to disaster management, we should keep the following things at home and check regularly.
1. Keep proper first aid kit at a handy place.
2. Keep all the electric connections in proper condition.
3. Keep the gas line or tube connection proper.
4. Keep self-powered flashlights and self-powered radios.
5. Keep non-perishable food which will last for a week.
6. Keep a fire extinguisher handy and in proper condition.
7. Keep updated telephone diary which should have emergency phone numbers.
In simple words: For disaster preparedness at home, one should regularly check the first aid kit, electrical and gas connections, ensure self-powered lights and radio are available, stock non-perishable food, have a fire extinguisher, and maintain an updated emergency contact list.

🎯 Exam Tip: Focus on items related to safety, communication, and basic survival needs within the household context.

Project:

Question 1.
With the help of the Internet, collect information about the places where a calamity has occurred.
Answer: Students are expected to research and compile information on various calamity-stricken locations, noting the type of disaster and its impact.
In simple words: This project involves using online resources to find examples of places where different types of disasters have happened.

🎯 Exam Tip: For project-based questions, describe the expected output in terms of research and information gathering.

Question 2.
Collect information from the Internet about how cyclonic storms are named.
Answer: Students are expected to research the international system and regional protocols for naming cyclonic storms, including the rotational lists and criteria.
In simple words: This task requires researching how cyclonic storms get their names, which typically follows an organized system agreed upon internationally.

🎯 Exam Tip: When addressing research-based questions, guide students to explore established naming conventions and regional bodies responsible for them.

Fill In The Blanks:

Question 1.
........... and ............ disasters are related to each other.
Answer:
Natural manmade.
In simple words: Natural and man-made disasters are interconnected, as human actions can exacerbate natural hazards, and natural events can cause man-made crises.

🎯 Exam Tip: Understand that disasters often have complex origins, sometimes involving both natural phenomena and human factors.

Question 2.
......... implemented a canal scheme for drinking water in Aurangabad.
Answer:
Malik Ambar.
In simple words: Malik Ambar was responsible for initiating a canal system to provide drinking water in Aurangabad.

🎯 Exam Tip: Specific historical facts or figures related to infrastructure development are important for general knowledge questions.

Question 3.
........... has turned out to be the most famine-affected contents of the world.
Answer:
Asia
In simple words: Asia has historically been the continent most severely impacted by famine worldwide.

🎯 Exam Tip: Geographic knowledge of disaster vulnerability can be a key scoring point.

Question 4.
The government of India established the ............ in 1976.
Answer:
National Flood Commission
In simple words: India's government established the National Flood Commission in 1976 to address flood-related issues.

🎯 Exam Tip: Knowing key government bodies and their formation years shows a good grasp of national disaster management initiatives.

Question 5.
The ............ that occurred in Mumbai on 26th August 2005 was extraordinary and unforgettable.
Answer:
cloudburst.
In simple words: The cloudburst that hit Mumbai on August 26, 2005, was a significant and memorable event due to its intensity and impact.

🎯 Exam Tip: Recalling specific historical disaster events and their types demonstrates contextual knowledge.

Question 6.
A cloudburst occurred at ............ on 6th August, 2010.
Answer:
Ladakh (Leh)
In simple words: A cloudburst event took place in Ladakh (Leh) on August 6, 2010.

🎯 Exam Tip: Linking specific dates to disaster locations can be important for factual recall.

Question 7.
About ............ lightning flashes occur per second in the atmosphere.
Answer:
40.
In simple words: Approximately 40 lightning flashes are estimated to occur in the Earth's atmosphere every second.

🎯 Exam Tip: Numerical facts related to natural phenomena are often tested for accuracy.

Question 8.
The temperature generated by ............ is higher than that of the sun.
Answer:
lightning
In simple words: The core temperature of a lightning bolt is hotter than the surface of the sun.

🎯 Exam Tip: Highlighting extreme characteristics of natural phenomena, like lightning's temperature, can be an interesting fact to remember.

Question 9.
When some substances comes out of the earth's crust in an eruption and start flowing is called a ............
Answer:
volcano
In simple words: The geological process where molten rock, ash, and gases erupt and flow from the Earth's crust is called a volcano.

🎯 Exam Tip: Basic definitions of geological events are fundamental to understanding natural disasters.

Question 10.
Some islands are created due to the eruption, of ............ in the sea.
Answer:
volcano
In simple words: Volcanic eruptions beneath the sea can lead to the formation of new islands.

🎯 Exam Tip: Understand how geological processes like volcanic eruptions can shape the Earth's surface and create new landforms.

Question 11.
............ is a Japanese word which means 'harbour wave'.
Answer:
Tsunami.
In simple words: The word 'Tsunami' originates from Japanese, meaning 'harbour wave'.

🎯 Exam Tip: Knowing the etymology of scientific terms can provide deeper insight and improve recall.

Question 12.
About ............ nations from all over the world are members of the UNDP.
Answer:
177.
In simple words: Approximately 177 countries globally are part of the United Nations Development Programme (UNDP).

🎯 Exam Tip: Factual information about international organizations and their membership numbers is often important.

Question 13.
............ established a standing international organization UNDP in 1965.
Answer:
United Nations.
In simple words: The United Nations established the UNDP in 1965 as a global development organization.

🎯 Exam Tip: Associate key international organizations with their founding bodies and dates.

Question 14.
............ is celebrated as International Day for Disaster Reduction.
Answer:
13th October
In simple words: October 13th is designated as the International Day for Disaster Reduction.

🎯 Exam Tip: Important international days related to global issues like disaster reduction should be remembered.

Question 15.
The condition that arises due to long term and severe scarcity of food grains and water is called...........
Answer:
famine
In simple words: A prolonged and severe shortage of food and water leading to widespread hunger is defined as famine.

🎯 Exam Tip: Understand the precise definition and conditions that lead to specific disaster types like famine.

Can You Tell?

Question 1.
Is it possible to prevent the loss of life caused by lightning?
Answer:
Yes, it is possible to prevent the loss of life caused by lightning, by taking precautions.
In simple words: Yes, by following safety guidelines and taking necessary precautions, it is indeed possible to prevent fatalities from lightning strikes.

🎯 Exam Tip: Emphasize that while lightning cannot be prevented, its dangers to human life can be mitigated through awareness and precaution.

Question 2.
What should be done to prevent the bunds on a farm from getting washed away in the rainy season?
Answer:
1. Grow more trees near the bunds.
2. Grow grass strips.
3. Make stone lines near the bunds.
4. Use contour ploughing and tillage network method to prevent the bunds on a farm from getting washed away in the rainy season.
In simple words: To protect farm bunds from washing away during heavy rains, measures include planting trees and grass, building stone lines, and implementing contour ploughing or tillage networks.

🎯 Exam Tip: Focus on soil conservation techniques that enhance soil stability and reduce erosion during rainfall.

Question 3.
Why do we experience water scarcity?
Answer:
Lessor no rain leads to water scarcity.
In simple words: Water scarcity primarily occurs due to insufficient or no rainfall, leading to a shortage of water resources.

🎯 Exam Tip: The most direct cause of water scarcity in many regions is inadequate precipitation, so focus on that key factor.

Question 4.
What causes rain?
Answer:
1. Due to heat of the sun, water from the sea, lake and river gets evaporated and this water vapour is light in weight so it goes higher and higher and forms the cloud.
2. At a certain level the amount of vapour in those clouds becomes very heavy and it burst and rain occurs.
In simple words: Rain is caused by the sun's heat evaporating water, forming water vapor that rises and condenses into clouds; when these clouds become saturated and heavy, the water falls back to Earth as rain.

🎯 Exam Tip: Explain the complete water cycle briefly, from evaporation to condensation and precipitation.

Question 5.
Have you seen a flash of lightning in the sky? When?
Answer:
Students will answer this question based on their experience.
In simple words: This question asks students to recall their personal experiences of seeing lightning flashes, including the circumstances when they observed them.

🎯 Exam Tip: Encourage students to connect theoretical knowledge with real-world observations for better understanding.

Question 6.
What causes lightning?
Answer:
1. Where air and clouds rub against each other in the sky, the upper part of some clouds on the upper side becomes positively charged and the lower sides become negatively charged.
2. When this negative charge on the bottom of the cloud becomes much larger than the charge on the ground it starts flowing towards the ground in stages.
3. This happens very fast, in much less than a second and heat, light and sound energy are produced along with the electric current.
In simple words: Lightning is caused by a rapid discharge of static electricity that builds up in clouds due to friction between air currents and ice particles, creating an imbalance of charges that eventually seeks to equalize with the ground or other clouds.

🎯 Exam Tip: Focus on the concept of charge separation within clouds and the rapid discharge as the core explanation for lightning.

Use Your Brainpower!

Answer The Following Questions:

Question 1.
We should not wait at the foothill while it is raining heavily.
Answer:
During heavy rain there are chances of landslide and flood, so we should not wait at the foothill while it is raining heavily.
In simple words: It is unsafe to wait at foothills during heavy rain because such areas are highly prone to landslides and flash floods, posing significant danger.

🎯 Exam Tip: Highlight the specific risks (landslides, flash floods) associated with foothills during heavy rainfall.