Question

Question

Answer 1

@dan815

Answer 2

ok yep?

Answer 3

what is the question

Answer 4

so when i put all the values in the calc i dont get excat answer as tht

Answer 5

http://www.wolframalpha.com/input/?i=4.14*10^-15+*3*10^8%2F2.55

Answer 6

seems to be right

Answer 7

no i mean the answer is right but this is what i get when i put in the excat value

Answer 8

what do you get?

Answer 9

4.8705*10^-7

Answer 10

okay lets do by this way.....

Answer 11

multiply by 4.14*3 . and in powers of 10, add -15 and 8, we get -7, isn't it

Answer 12

ok

Answer 13

now 4.14*3 we get 12.4, now divide it by 2.55.

Answer 14

so total we have 4.87 * 10^-7, isn't it?
And you have a problem that it is 487, right?

Answer 15

ok

Answer 16

Nanometer is 10^-9, the answer you got was 10^-7, so just some need to do conversion and you get the numbers.

Answer 17

now listen carefully 1nm=10^-9m, right?
so,when we have 4.87*10^-7 if we take it to nanometer, 100 is multiplied to 4.87

Answer 18

and 100 is divided in 10th power to make it to nanometer.....

Answer 19

so, you get 487*10^-9, Got it?

Answer 20

is their a single number i can just times by

Answer 21

I didn't get you, single number?

Answer 22

yea like when we have somthing in grams we just divide by 1000 to get in kg

Answer 23

0.000000001

Answer 24

yes, yes

Answer 25

10^-9 is 0.000000001
10^-7 is 0.0000001

Answer 26

in my data shhet i have to h values one in ev and the other in J which one to use?

Answer 27

eV

Answer 28

how know for sho

Answer 29

1eV=1.602*10^-19 J

Answer 30

you can convert and write anyone.... its your choice....

Answer 31

if the question is in ev then i use ev right

Answer 32

yes.. ofcourse

Answer 33

But you can use Joules, but it will just become complicated...

Answer 34

Got it?

Answer 35

yea

Answer 36

i hav e anotehr

Answer 37

i was doing these practive probs but wasnt getting the right answer doww

Answer 38

frequineces required for photoelectron emsiion in 400 THz

Answer 39

ya, i will try ask

Answer 40

wavelength 500nm what is speed if excaping eletrons ?

Answer 41

tell me waht u get for speed

Answer 42

from which orbit are the electrons escaping?

Answer 43

doesnt say anthing else

Answer 44

their was a work funstion 2.65*10^-19

Answer 45

ya work function....

Answer 46

Wait

Answer 47

The minimum energy required to make an electron free from the metal is called the work function, right?

Answer 48

ye

Answer 49

okay I got it....... use this

Answer 50

hc/lambda=workfunction+K.E

Answer 51

K.E is kinetic energy

Answer 52

and K.E=1/2mv^2

Answer 53

so you can get v from here.... rest all data given h,c,lambda,mass of electron and work function

Answer 54

just plug in the values... you will get the answer. Got it?

Answer 55

Ek=hc/wavelenght

Answer 56

i tried i didnt get btw what u get

Answer 57

so, do you have the answer with you? I will solve and ask you

Answer 58

yes

Answer 59

9.33 * 10^21

Answer 60

long calculation

Answer 61

its 5.40*10^5

Answer 62

hmmm

Answer 63

but the process is this way.... well I was of no use... sorry... I did my best....