PTE

the presence or introduction of substances or energy that harm the environment

to process used or discarded material so that it can be made into useful material or products again

to use an item again, for its original purpose or a different one, instead of discarding it

the natural material near the land surface, containing minerals and organic matter, in which many plants grow

to remove unwanted plants from an area where other plants are being grown

the rate at which air moves past a particular point

shaking of the ground caused by a sudden release of energy within Earth, often when rock slips along a fault

a representation of an area that shows the locations and spatial relationships of selected features

an area identified by shared features or defined boundaries for a particular description or purpose

a natural object that orbits a planet or another larger body

a major, nearly round body orbiting a star; in the solar system, it has also cleared its orbital neighborhood

relating to the Sun or its energy

the Sun and the planets, moons, and other objects gravitationally associated with it

a large, self-gravitating body that produces light and is powered by nuclear fusion during its active life

an instrument that collects radiation from distant objects to form images or obtain information about them

phenomena associated with electric charge, especially its movement and use to transfer energy

a physical quantity that can be transferred between systems, for example through work or heat

a push or pull arising from an interaction that can change an object's motion or shape

a form of matter that has no fixed shape or volume and expands to fill available space

energy transferred between systems because their temperatures differ

electromagnetic radiation that can be detected by the human eye

a flowing form of matter with a definite volume but no fixed shape of its own

a physical quantity measuring an object's inertia, distinct from the gravitational force acting on it

physical material that has mass and occupies space

to change from a solid into a liquid because of heat, or to cause this change

an element or material typically able to conduct heat and electricity and often capable of being shaped

a change in position relative to a chosen reference over time

a material based mainly on polymers that can be shaped during manufacturing and may contain additives

a form of matter that retains a definite volume and shape under ordinary conditions