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Radioactivity and radiation

alpha particle

noun

the nucleus of a helium atom that is produced by some radioactive substances

atomic

adjective

relating to or using the energy that is produced by splitting atoms (=breaking them apart)

becquerel

noun

a unit for measuring radioactivity

carbon dating

noun

a method of finding out the age of a very old object by measuring the amount of radioactive carbon it contains

cosmic radiation

noun

a form of radiation that reaches the Earth from space

cosmic rays

noun

cosmic radiation

electrosmog

noun

the electromagnetic radiation from computers and mobile phones, that some people think is harmful to health

fission

noun

the process of dividing an atom in order to create energy

gamma rays

noun

a type of radiation with a very short wavelength that can pass through solid objects

Geiger counter

noun

a piece of equipment that finds and measures radioactivity

half-life

noun

the amount of time that is needed for a substance to lose one half of its radioactivity

microwave

noun

a type of electromagnetic wave used in radio communication, radar, and cooking

plutonium

noun

a radioactive substance used in making nuclear power

radiant

adjective

radiant heat is the energy produced by hot objects. It is in the form of infrared light that cannot be seen.

radiation

noun

a form of energy produced during a nuclear reaction that is used for making electrical power but can also kill or harm humans who receive too much of it

radiation

noun

consisting of radiation, or caused by radiation

radiation

noun

a type of energy that is sent out in the form of electromagnetic waves, for example, heat, light, or radio waves

radioactive

adjective

a radioactive substance contains a very harmful form of energy that is produced during nuclear reactions. This energy is called radiation.

radioactive waste

noun

the harmful waste that is produced while making nuclear energy

radioactivity

noun

a form of energy that is produced by a radioactive substance and is harmful in large amounts

radioactivity

noun

the ability that some substances have to produce energy in the form of radiation

radium

noun

a radioactive element used in the treatment of cancer

radon

noun

a type of radioactive gas that is produced when radium separates into the parts it is made of

unstable

adjective

relating to a radioactive substance whose nucleus breaks down to release radioactivity

uranium

noun

a chemical element that is a metal and is used for producing nuclear energy because it is radioactive

X-ray

noun

a type of radiation that is used for looking inside things, for example your body or a suitcase at an airport

kabaddi

a game in which two teams of seven players take turns to chase and try to touch players on the opposing team

BuzzWord Article

Open Dictionary

Ouch!

a response to a scathing comment or unpleasant situation

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