Copy and complete the table using the words given below: Geiger counter/ alpha/ gamma/ background radiation/ photographic film/ beta Radiation in the environment Detectors of ionising radiation Three types of ionising radiation from radioactive substances

Radiation in the environment background radiation Detectors of ionising radiation Geiger counter Three types of ionising radiation from radioactive substances alpha, beta, gamma Environmental radiation exists in our surroundings as a result of both natural and man-made sources. Environmental radiation is frequently referred to as background radiation. The majority of background radiation is emitted naturally by minerals, with only a minor percentage emitted by man-made components. Background radiation is produced by naturally occurring radioactive minerals in the earth, soil, and water. A Geiger counter (also known as a Geiger-Muller tube) is a device that detects and measures all forms of radiation, including alpha, beta, and gamma radiation. It is made up of a pair of electrodes that are surrounded by a gas. The main three types of ionising radiation from radioactive substances are alpha, beta and gamma. The charge of alpha particles is positive, the charge of beta particles is negative, and the charge of gamma rays is zero.

Copy and complete the table, which summarises how radiations are absorbed. Radiation Penetration Absorption Absorbed by Alpha Least penetrating most easily absorbed thin paper, a few cm of air Beta in between Gamma

Radiation Penetration Absorption Absorbed by Alpha Least penetrating most easily absorbed thin paper, a few cm of air Beta in between in between thin metal foil Gamma Most penetrating least easily absorbed thick lead or concrete The alpha radiation is the least penetrating, and its will be most absorbed. It can be absorbed by thin paper. The beta radiation is having penetration in between the alpha and gamma radiations. Absorption rate is also in between the alpha and gamma radiations. It can be absorbed by a thin metal foil. The gamma radiation is the most penetrating radiation. It is the least absorbed and it can even be absorbed by thick lead or even concrete. It is having neutral charge.

E M B I B E

Cambridge IGCSE® Physics Coursebook Second Edition>Chapter 23 - Radioactivity>End-of-chapter questions>Q 1

EASY

Upper Secondary: IGCSE

IMPORTANT

Earn 100

Alpha, beta and gamma radiations are the three types of radiation produced by radioactive substances. Copy and complete the table to show the nature of these radiations.

Radiation Symbol Type of particle or electromagnetic radiation Mass Charge

Alpha

Beta

Gamma

Important Questions on Radioactivity

EASY

Upper Secondary: IGCSE

IMPORTANT

Cambridge IGCSE® Physics Coursebook Second Edition>Chapter 23 - Radioactivity>End-of-chapter questions>Q 2

Copy and complete the table using the words given below:

Geiger counter/ alpha/ gamma/ background radiation/ photographic film/ beta

Radiation in the environment
Detectors of ionising radiation
Three types of ionising radiation from radioactive substances

EASY

Upper Secondary: IGCSE

IMPORTANT

Cambridge IGCSE® Physics Coursebook Second Edition>Chapter 23 - Radioactivity>End-of-chapter questions>Q 3

Beta radiation is attracted towards a positively charged plate because _____.( it is negatively charged/ it is having neutral charge)

EASY

Upper Secondary: IGCSE

IMPORTANT

Cambridge IGCSE® Physics Coursebook Second Edition>Chapter 23 - Radioactivity>End-of-chapter questions>Q 4

Copy and complete the table, which summarises how radiations are absorbed.

Radiation	Penetration	Absorption	Absorbed by
Alpha	Least penetrating	most easily absorbed	thin paper, a few cm of air
Beta	in between
Gamma

MEDIUM

Upper Secondary: IGCSE

IMPORTANT

Cambridge IGCSE® Physics Coursebook Second Edition>Chapter 23 - Radioactivity>End-of-chapter questions>Q 5

Sketch a graph to show the pattern of radioactive decay. Indicate how the half-life is found from the graph.

EASY

Upper Secondary: IGCSE

IMPORTANT

Cambridge IGCSE® Physics Coursebook Second Edition>Chapter 23 - Radioactivity>End-of-chapter questions>Q 7

A school has two radioactive sources for use in physics experiments. One is a source of

α

- radiation, and the other is a source of

β

- radiation. They have lost the labels, and the teacher wants to check which is which. Use your knowledge of the different penetrating powers of these radiations to suggest how this might be done.