Question

What are ergs?

Answer 1

C.G.S unit of work...
1 erg=1dyn*1cm

Answer 2

What is a dyn /

Answer 3

C.G.S unit of force...
1 dyn=1g*1cm per second per second

Answer 4

So that makes

\[[\text{dyn}]=1[\text g][\text{cm}][\text s]^{-2}=10^{−5}[\text N]\]
right?

Answer 5

yeah..

Answer 6

and

\[[\text{erg}]=1[\text {dyn}][\text{cm}]\\
\qquad=10^{-5}[\text N]\times10^{-2}[\text m]\\
\qquad=10^{-7}[\text J]\]
right?

Answer 7

right..

Answer 8

where are these exotic units the dyne and erg used?

Answer 9

In real life SI units are used..

Answer 10

yeah good,
im doing a course in nuclear science atm

and i dont know why they professor uses ergs, i guess it's a usa thing.

Answer 11

\[Q=45[\text{mCi}]\\E'=5.407[\text{MeV}]=8.66\times10^{-13}[\text J]=8.66\times10^{-6}[\text{erg}]\\m=2000[\text{g}]=2[\text{kg}]\]

Answer 12

\[R_p(t)=\frac{Q(t)E'}m\\\qquad=\frac{45\times10^{-3}[\text{Ci}]\times8.66\times10^{-13}[\text J]}{2[\text{kg}]}\\
\qquad=1.946\times10^{-13}\frac{[\text{Ci}][\text J]}{[\text{kg}]}\]

Answer 13

is Ci means Curie?

Answer 14

yes

Answer 15

SI unit of disintegration constant is Becqueral (Bq) ... right?

Answer 16

yes one [Bq] is one disintegration per second

Answer 17

if you are using SI units...you would take all the quantities in same system of unit..

Answer 18

ook so i have to convert those Curies to Becquerel right?

Answer 19

\[[\text{Ci}]=3.7\times10^{10}[\text{Bq}]\]

Answer 20

yeah

Answer 21

\[Q=45[\text{mCi}]\\\qquad=45\times10^{-2}[\text{Ci}]\times\frac{3.7\times10^{10}[\text{Bq}]}{[\text{Ci}]}\\
\qquad=1.62\times10^{10}[\text{Bq}]\]

Answer 22

\[R_p(t)=\frac{Q(t)E'}m\\\qquad=\frac{1.62\times10^{10}[\text{Bq}]\times8.66\times10^{-13}[\text J]}{2[\text{kg}]}\\
\qquad=7.02\times10^{-3}\frac{[\text{Bq}][\text J]}{[\text{kg}]}\]

Answer 23

mCi....m stands for mili Curie..?
so 1mCi=10^-3 Ci

Answer 24

whops! you right .

Answer 25

7.02E-4

Answer 26

um,

Q=45[mCi]=1.66E9[Bq]

Answer 27

what a mess, im confused

Answer 28

What is R?

Answer 29

is this right

Answer 30

How do i make the units better

Answer 31

which unit?

Answer 32

[Bq].[J] / [kg] =?

Answer 33

or are they the correct units for dose rate?

Answer 34

i think its okay...
what is the CGS unit of this rate?

Answer 35

i dont like C.G.S. :(

Answer 36

as Joule =kg*meter/sec^2
so Joule/kg=meter/sec^2
so you can write Bq*m/s^2
i dont know is it the unit of this rate..

Answer 37

Yeah ok [Bq][m]/[s^2]
that works too
i spose that would be like the attenuation

[Bq][J]/[kg] is starting to make sense as a choice of unit because the energy is being delivered to the mass.

Answer 38

Thanks for all your help @souvik