Volcanoes

Which characteristic of magma mainly determines its explosiveness?

• color

• amount

• temperature

• silica content

Which of the following characteristics of a volcano depends on its magma emission?

• age

• size

• shape

• location

Which of the following factors associated with huge volcanic eruptions may cause the decrease in the Earth's average temperature for a few years?

• heat

• light

• acid rain

• volcanic ash

A thick layer of volcanic ash can be heavy enough to collapse the roots of buildings because ash_______

• is solid

• cannot be blown by winds

• becomes heavier as it cools

• consists of tiny fragments of rocks that becomes heavy as they pile up.

Which type of energy can be obtained from the Earth's interior?

(a)  

What happens to the temperature of air when altitude increases?

• remains the same

• increases

• decreases

• varies

Which of the following best describes climate?

• The weather that occurs in the atmosphere within a day.

• The pattern of weather that occurs in a region over a long period of time.

• The pattern of weather that occurs in a region over a short period of time.

• The disturbance in the atmosphere that happens in a long period of time.

How does the windward side differ from the leeward side of a high land?

• The windward receives more precipitation than the leeward.

• The leeward side has more vegetation than the windward side.

• The windward side receives more heat than the leeward side.

• The leeward side receives more precipitation than the windward side.

How do stars appear to move in the night sky?

• from east to west

• from north to south

• from west to east

• from south to north

Why do stars have colors?

• because of the presence of oxygen

• because of the presence of carbon dioxide

• because of varied temperatures

• because of different locations