Physics presentation

GROUP MEMBER

Form 4 Physics Presentation

Aric Chieng Lai Fook ChernJared LimLing Sung EngWong Yueh kaI

WHAT IS A VOLCANO?

• A volcano is a vent or 'chimney' that connects molten rock (magma) to the Earth's surface. It includes the surrounding cone of built-up material. Magma erupting from a volcano is called lava. Gases and pieces of rock erupt from volcanoes too.

• A volcano is active if it erupts lava, releases gas or shows seismic activity. It is dormant if it hasn't erupted for a long time but could again one day. An extinct volcano will never erupt again.

Effect Of Volcano• The first is how the weather near an erupting volcano

is being affected. The second is how large eruptions will affect the weather/climate around the world. I think more people are worried about the second issue than the first. As far as we know, the main effect on weather right near a volcano is that there is often a lot of rain, lightning, and thunder during an eruption. This is because all the ash particles that are thrown up into the atmosphere are good at attracting/collecting water droplets. Another problem in Hawaii is that involves the formation of volcanic fog. The ongoing eruption is very quiet, with lava flowing through lava tubes and then into the ocean.

Types of Volcanoes There are two main types of volcanoes: shield and

composite. Shield volcanoes are usually found in the middle of tectonic plates. Islands like Hawai'i are good examples of this type of volcano. There's a hole in the middle of the plate and magma moves out and piles on top of itself, slowly building a mountain of rock. That magma comes from small tunnels which scientists call vents.

The other big type is a composite volcano. This type of volcano is usually what you think of as a volcano. It's shaped like a cone and mainly made up of ash, which has piled up and compacted over the years. You'd find these volcanoes in subduction zones like Mount Ararat in Turkey. The stuff that comes out is smaller. There's not so much lava but lots of small rocks and a lot of ash. Those rocks are called pyroclastic.

Volcanic structure

How Volcanoes Erupt• While the shape and size or a volcano may vary the way that it

erupts does not. Every volcano has what is known as a magma chamber. This is where hot, molten rock from the earth’s mantle collects. The process of a volcano erupting begins when the pressure in a magma chamber begins to build. This may be caused by the movement of the tectonic plates forcing the magma into smaller areas or the buildup of gases as more magma fills the chamber as plates move apart. The building pressure causes the magma to rise up a series of conduits inside the volcano. When it reaches the fissure or crack at the top of the volcano it erupts. The size of the eruptions depends on a number of factors such as:

• How much magma is in the chamber prior to eruption • How much gas is present in the chamber and the magma itself • How much silica is in the magma • If there was any water present

Project: How to make a Volcano Model

MATERIALSGlueNewspaperVinegarBaking sodaRed food colouringFew drop of dish soapPaint

Procedure 1. Bottle is glue to a cardboard base.

2. Newspaper is used to build up the volcano.

3. Volcano is mould to any shape you like.

4. After glue is dried,the volcano is painted by using different colours as you like.

5. Baking soda and dish soap is added.

6. Then,half of the bottle of vinegar is added with a few drops of red food colouring.

7. Later,volcano erruption is happened.When it begins to bubble,the rest of the vinegar is slowly pour.

Image Steps to Make Volcano ModelExample:

• Example