## anonymous 3 years ago PLEASE HELP medical x-rays, with a wavelength of about 10^-10m, can penetrate completely through your skin. Ultra violet rays, which cause sunburns by penetrating only the top level of skin, have a wavelength about 1000 times the wavelength of an x-ray. find the wavelength of ultraviolet rays. show your work. Hint: scientific notation.

1. AravindG

first did you get the wavelength of ultraviolet rays ?

2. anonymous

no i was going with 1000 x 10^-10 but thats not right.

3. AravindG

you are right !

4. anonymous

thats all i do?

5. AravindG

now just ensure you report answer in scientific notation

6. AravindG

ie in the form $a \times 10^b$

7. anonymous

|dw:1359548779460:dw|

8. anonymous

i have just use the scientific notation form

9. anonymous

so i dont have to solve it? and @manishsatywali why +3 to the exponent?

10. AravindG

@manishsatywali we at openstudy do not appreciate giving direct worked out answers like that .Instead help the user get to the answer. Refer openstudy COC http://openstudy.com/code-of-conduct

11. anonymous

I HAVE USED THE PROPERTY : M ^n * M ^ b = M ^(n+b)

12. anonymous

???

13. anonymous

here M = 10 and n = 3 , b = -10

14. anonymous

did u get that ?

15. anonymous

whats the n for?

16. anonymous

n = 3

17. anonymous

10^3 * 10^(-10)

18. anonymous

but why do you need 10^3? where does it come from in the problem?

19. anonymous

1000 = 10 ^3

20. anonymous

wouldnt that be 1 x 10^3?

21. AravindG

$10^3=1 \times 10^3$

22. anonymous

@AravindG IS RIGHT DO U FOLLOW HIM NOW ?

23. anonymous

so thats how i get the -10+3?

24. anonymous

yup

25. AravindG

yep :)

26. anonymous

now u understand what i was trying to say

27. anonymous

so it would be (1 x 10^-10)(1 x 10^3) ? which simplifies to 1 x 10^-7?

28. anonymous

right?

29. anonymous

yes u got it

30. anonymous

ok :) thanks.