Physics 5

Question 1

• Power - the amount of energy transferred in one second.

Question 2

Kinetic and Gravitational potential energy

Question 3

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Question 4

Kinetic energy - the energy a body has due to its motion.

Question 5

Gravitational potential energy - the energy a body has due to its height above the earth’s surface.

Question 6

Structure of the nucleus

Question 7

• Mass number - the number of protons and neutrons in an atom.

Question 8

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Question 9

Atomic number - the number of protons in an atom.

Question 10

Relative mass of an electron - 1/1840.

Question 11

Isotope- atoms of the same element with the same atomic number but different mass numbers.

Question 12

Radioactive decay

Question 13

• Radioactive - when an unstable nucleus decays to become more stable giving out some form of

Question 14

radiation e.g. alpha

Answer 14

beta

Question 15

Alpha particle - a particle consisting of 2 neutrons and 2 protons emitted from an unstable nucleus

Question 16

in radioactive decay.

Question 17

Beta particle - a fast moving electron emitted from an unstable nucleus in radioactive decay.

Question 18

Gamma ray - high energy electromagnetic wave emitted from an unstable nucleus in radioactive

Question 19

decay•

Question 20

Background activity - this is the activity that can be measured when all other known sources of

Question 21

radiation are removed from the area.

Question 22

Half-life

Question 23

• Half-life - the time taken for the count rate of a radioactive source to halve.

Question 24

Nuclear fission

Question 25

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Question 26

Fission - when a heavy nucleus e.g. uranium

Answer 26

absorbs a neutron and splits into two lighter nuclei

Question 27

emitting 2/3 neutrons and energy.

Question 28

Nuclear fusion

Question 29

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Question 30

Fusion - when two light nuclei e.g. hydrogen are joined together producing a heavier more stable

Question 31

nucleus (e.g. helium) giving out energy.