Relating to or denoting the generation of electricity using flowing water is called ____.
Hydroelectric.
100
When a solid is heated and turns into a liquid, it's called ____.
Melting.
100
What is an activity involving mental or physical effort done in order to achieve a purpose or result?
Work.
100
This is the top layer of the Earth. It is divided into huge plates that float on the mantle.
The crust.
100
This atmosphere starts abovve the mesosphere and extends to 600 kilometers high. Aurora and satelites occur in this atmosphere
The thermosphere.
200
A liquid derived from petroleum is ____.
Oil.
200
The process by which heat or electricity is directly transmitted through a substance when there is a difference of temperature is called ____.
Conduction.
200
When water is heated it turns into a gas it is called ____.
Vaporization.
200
This layer is composed of a nickel-alloy. It is about 1355 miles thick.
The outer core.
200
This atmosphere starts just above the troposphere and extends 50 kilometers high. It contains the ozone layer.
The stratosphere.
300
Energy coming from or relating to the nucleus of an atom is called ____ energy.
Nuclear.
300
The emission of energy as electromagnetic waves is called ____.
Radiation.
300
When a substance changes from a liquid to a solid it is called ____.
Freezing.
300
This layer is about 1,800 miles deep. It is mostly silicate rock rich in magnesium and iron.
The mantle.
300
This atmosphere layer starts just above the stratosphere and extends to 85 kilometers high. Meteors start to burn in this region, and we know them as shooting stars.
The mesosphere.
400
Energy of, relating to, or produced by the internal heat of the earth is called ____ energy.
Geothermal.
400
The degree or intensity of heat present in a substance or object is it's ____.
Temperature.
400
When a substance changes directly from a solid to a gas without being a liquid it is called ____.
Sublimation.
400
This layer is made of iron has a radius of about 760 miles. It is surrounded by a liquid.
The inner core.
400
This atmosphere starts at the Earth's surface and extends 8 to 145 kilometers high. All weather occurs here.
The troposphere.
500
A combustible black or dark brown rock consisting mainly of carbonized plant matter is ____.
Coal.
500
The movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink is called ____.
Convection.
500
When a substance changes from a gas to a liquid it is called ____.
Condensation.
500
This layer is divided in to an upper and lower layer.