topics 2-4

Question 1

SI units for length

Answer 1

metres

Question 2

SI units for mass

Answer 2

kilogram

Question 3

SI units for time

Answer 3

seconds

Question 4

SI units for temperature

Answer 4

Kelvin

Question 5

SI units for current

Answer 5

Ampere

Question 6

Newton units

Answer 6

Kg . m . s^-2

Question 7

velocity equation

Answer 7

d / t

Question 8

acceleration equation

Answer 8

v / t

Question 9

weight equation

Answer 9

m . g (gravity of earth)

Question 10

momentum equation

Answer 10

m . v

Question 11

work equation

Answer 11

F . d

Question 12

Force units

Answer 12

Newton

Question 13

power equation

Answer 13

work / t (Fd/t)

Question 14

power units

Answer 14

watts (joule/second)

Question 15

energy definition

Answer 15

the ability to do work

Question 16

energy units

Answer 16

joule = ( kg . m^2 )/ s^2

Question 17

kinetic energy equation

Answer 17

1/2 m.v^2

Question 18

kinetic energy units

Answer 18

joules

Question 19

kinetic energy equation in terms of electrons

Answer 19

e. V
elementary charge = 1.602 x 10^-19 C
V = voltage

Question 20

whats one electron volt

Answer 20

the energy gained by 1 electron through 1 volt

Question 21

potential energy equation

Answer 21

m . g . h

Question 22

potential energy units

Answer 22

joule

Question 23

joule units

Answer 23

( kg . m^2 )/ s^2

Question 24

Force equation

Answer 24

m . a (acceleration)

Question 25

why is weight measured in newtons

Answer 25

it is a type of force

Question 26

what is atomic mass unit

Answer 26

the approx mass of proton or neutron

Question 27

whats isotope

Answer 27

P = same no of protons (Z)

Question 28

whats isotone

Answer 28

N = same no of n (neutrons)

Question 29

whats isobars

Answer 29

same A (number of nucleons)

Question 30

whats radioactivity

Answer 30

the spontaneous emission of energy when atoms goes from energetic to lower energy for stabilise

Question 31

what are the two types of radiation

Answer 31

particulate and electromagnetic

Question 32

whats particulate radiation

Answer 32

radiation involving particles with mass eg alpha and beta radiations

Question 33

whats electromagnetic radiation

Answer 33

radiation involving energy waves without mass eg gamma rays and xrays

Question 34

whats the atomic difference in alpha radiation

Answer 34

A - 4 , Z - 2 (because helium is produced and it has A4, Z2) lighter by 4 amu

Question 35

whats negative beta electron decay

Answer 35

nuclei with excess electrons will decay neutron changes into proton, electron (-beta), anti-neutrino

Question 36

whats anti neutrino

Answer 36

packets of energy (no charge) released to conserve energy + momentum

Question 37

whats positive beta decay

Answer 37

nuclei with excess protons will decay proton turn into neutron, positron and neutrino

Question 38

when does alpha radiation occur

Answer 38

when A is big, N > Z

Question 39

SI unit of radioactive activity

Answer 39

becquerel (Bq)

Question 40

whats radionuclides

Answer 40

nuclei that undergo radioactive decay

Question 41

whats the probability of decay proportional to

Answer 41

the number unstable nuclei present

Question 42

radioactivity decay equation

Answer 42

N(t) = initial atoms . e ^(-decay constant . t)

Question 43

half life equation

Answer 43

Ln(2) / decay constant

Question 44

gray units

Answer 44

J / Kg

Question 45

coloumb units

Answer 45

A . s

Question 46

coloumb constant units

Answer 46

N.m^2 / C^2

Question 47

ampere equation

Answer 47

C/s

Question 48

whats watt units

Answer 48

joule / second