Question

Significant figures help please?
Thanks. ^.^

Answer 1

3.5 x 10^3 * 2.11 x 10^4

Answer 2

So this one doesn't have any SI units..
Do I just simply multiply them then subtract the exponents?

Answer 3

@iambatman @ganeshie8

Answer 4

you're multiplying two numbers in scientific form

Answer 5

`3.5 x 10^3` * `2.11 x 10^4`

Answer 6

how many sigfigs are there in first number ?
how many sigfigs are there in second number ?

Answer 7

So 7.385 x 10(-1) ?

Answer 8

I mean 7.385 * 10^(-1)

Answer 9

\[\large a^m*a^n = a^{m\color{Red}{+}n}\]

Answer 10

Ah, so 7.385 * 10^7 ?

Answer 11

yes, fix the sigigs now

Answer 12

What is there to fix?

Answer 13

`3.5 x 10^3` * `2.11 x 10^4`

# of sigfigs in first number = 2
@ of sigfigs in second number = 3

Answer 14

so the result must be rounded to 2 sigfigs

Answer 15

7.385 * 10^7
^

Answer 16

round it

Answer 17

7.4

Answer 18

what happened to 10 powers ?

Answer 19

I dunno

Answer 20

7.385 * 10^7

rounded to two sigfigs would be :
7.4 * 10^7

Answer 21

7.385 * 10^7 is a very big number

it won't reduce to just 7.4 no matter how you round it

Answer 22

Okay, so we don't do anything different with the powers, correct?

Answer 23

correct !

Answer 24

if you're 174 cm,
you wont round it to 17cm when telling it to others

you would say either 170 cm or 200cm, but never 17cm

Answer 25

okay, but could you also say 180?

Answer 26

if your height is 176 cm, then rounding it to nearest 10cm gives you 180 cm

Answer 27

but 174cm can never round to 180cm

Answer 28

it always rounds to 170cm

Answer 29

That's true because 4 is closer to 0, right?

Answer 30

exactly !

Answer 31

Yay!! ^.^

Answer 32

Also, 174 rounds to 200 cm
but never 100cm

Answer 33

if you really have a stupid tape that can only measure in kilometers,
then your height would be 0km

Answer 34

because 174cm rounded to nearest kilometer is 0km

Answer 35

XD

Answer 36

That would suck haha

Answer 37

thats exactly what happens when scientists try to measure objects at nanometer level, their main problem is not having a good tape to measure atoms/electrons

Answer 38

Get a better tape then haha :p

Answer 39

they measure lengths using light

Answer 40

i think 15nm is the lowest possible size thats ever measured so far in electronics

Answer 41

o.o that sounds complicated haha

Answer 42

http://www.goldstandardsimulations.com/files/3313/3855/6814/fin-measurement.gif

Answer 43

o.o yep

Answer 44

here is a cool site that really makes you put things in perspective http://htwins.net/scale2/

Answer 45

10^-35m to 10^27m

Answer 46

is that powers of 10 video

Answer 47

Not a video an interactive scale haha

Answer 48

@Whitemonsterbunny17 measuring at nanometer is not that complicated
see this 2 min video
https://www.youtube.com/watch?v=RHAso1yM-D4&index=157&list=FLxw3dTJ33oQoOk0AxkUSHag

Answer 49

O.O I love that!! It's amazing!!

Answer 50

That's really cool @ganeshie8

Answer 51

That's amazing we can even do that...jeeze.

Answer 52

i remember that video because that kid understood how microprocessors are made without studying any physics :P and certainly she is motivated to study sciences ! i feel thats how we should teach current generation kids

Answer 53

Agreed, that video was fascinating, even without knowing all the aspects of all the technical stuff.

Answer 54

Yeah, that's really awesome ^.^