Page 110 - Active Science 5 Ebook and Activity
P. 110
3. If you are driving, stop your vehicle and come out in an open area.
4. Take shelter under a table or bed, if you are inside the room.
5. Never run.
6. Avoid standing near the things that can fall.
Activity 9.1
Ask your neighbours to take a step ahead to help the earthquake victims. See how many people
come forward and to what extent you would be able to lend a helping hand to the victims.
V olcanoes
Volcano is an opening on the surface Cinder Cone Volcano
Ash, cinders, and lava
of the earth from where hot, molten lava erupt explosively to form
comes out. As soon as the pressure rises a cone-shaped hill. Crater
up, eruption takes place. Rocks and gases
shoot up through the openings and fill
the air with lava. Eruption causes floods,
mudslides, falling ash, etc. A crack develops
where earth’s crust is weak called a vent.
The hot magma that comes out of the
earth’s surface is called lava.
Layers of cinders
There are three types of volcanoes –active, dormant and extinct.
1. Active Volcanoes
An active volcano is the one that has erupted at least once in the recent past. It is the
most dangerous type of volcano. Some of the most active volcanoes are Mount St. Helens,
Mount Lassen in the United States.
2. Dormant Volcanoes
These volcanoes have not erupted since long but may erupt again. Mauna Kea in Hawaii,
Mount Edziza in Canada and Narcondam in Andaman Islands of India are dormant
volcanoes.
3. Extinct Volcanoes
Volcanoes that are not expected to erupt in future are called extinct volcanoes. Mount Ashitaka,
Japan, Shiprock in the United States and Zuidwal in the Netherland are extinct volcanoes.
Disadvantages of Volcanic Eruption
• Ash discharged has negative results on the ozone layer.
• Spread of diseases.
110 Active Science-5

