Final Exam Study Guide Unit 2: Solar Energy (Science)

7th Grade MA Semester 2

Albedo

The measure of the reflectivity of a surface.

Specific Heat

The amount of measured joules of thermal energy needed to raise the temperature of 1kg by 1°

Radiation

The transfer of thermal energy by electromagnetic waves.

Conduction

The transfer of thermal energy by collisions between particlas of matter

Troposphere

The layer closest to the Earth’s surface. It holds most of the atmosphere’s mass. It is the region where the clouds form and where all weather happens.

Stratosphere

Contains the ozone layer that absorbs ultra violet rays from the Sun. This heats the stratosphere and protects us from radiation.

Mesosphere

The coldest layer of the atmosphere. At its outer reaches, called the mesopause, temperatures average -90°C. Most meteors burn up in this layer, creating shooting stars.

Thermosphere

The hottest layer because energy form the Sun hits here first. It contains a later of charged atoms and molecules known as the ionosphere.

Exosphere

The outermost layer. It is extremely thin and doesn't have a specific outer limit. atoms and molecules escape into space from this region.

Visible Light

The wave length that our eyes can see. Red is the longest, violet is the shortest.

Microwaves

Used in many types of communication signals such as cell phones, wi-fi, and Bluetooth and in microwave ovens.

Electromagnetic Spectrum

The range of all types of electromagnetic radiation.

Radio Waves

The largest wavelength in the spectrum. Used to transmit radio and TV signals around the Earth.

Infrared Waves

Means “below red” as heat it is used in toaster and grills. Used in electronics such as remote controls.

Gamma Rays

Produced by radiation elements. Cannot be seen or felt but can cause cancer. Also used to treat cancer.

X-Rays

Used to make images of the body. X-Rays pass easily through soft tissue, but not as easily through bone.

Ultraviolet Radiation

Found naturally in sunlight. Causes sunburn and cancer. Sunblock products protect against UV rays.

Place the following words in order according to their abilities to warm up and cool down: Water, Air, and Sand.

1) Air (2) Sand (3) Water

Water has a (———) specific heat than both air and sand.

Higher.

All electromagnetic waves travel through the vacuum of space at the (————).

Speed of Light.

Which area of Earth receives the most solar radiation? Why?

The equator because sunlight strikes Earths surface than at a high angle it is a 90° angle year round.

Which area of Earth receives the least amount of solar radiation? Why?

At the poles because of the Suns radiation hitting directly on the equator and skipping the poles.

Which absorbs more heat, darker colors or lighter colors? Why?

Darker, because they have a lower albedo which means they absorb more light.

Which has a higher albedo, lighter colors or darker colors?

Lighter colors have a higher albedo because they absorb more light.

The higher the (————) of the electromagnetic wave, the (——) the energy.

Frequency, Greater