## darkb0nebeauty one year ago Ultraviolent rays, which cause sun burn by penetrating only the top level of kin, have a wavelength about 1000 times the wavelength of an X-ray. Find the wavelength of ultraviolent rays. Show your work.

1. darkb0nebeauty

Medical X-rays, with a wavelength of about 10 ^-10m, can penetrate completely through you skin.

2. darkb0nebeauty

can u help me...

3. Frostbite

Why don't you just multiply the wavelength of an X-ray with 1000 in order to get the wavewength of a UV ray?

4. Frostbite

Not sure, but sounds like that it is only that.

5. Frostbite

beside we know that X-rays have a wavelength on about 100 nano meter.. if we take 10^-10 meter and convert to nano meters.. we get 0.1 nm. Multiply that with 1000 and you get 100 nm.

6. darkb0nebeauty

ok so 10^-10m * 1000

7. Frostbite

if I had to guess, yes. Because we know the multiplication factor and one of the wavelengths. However if I were you I would calculate in nano meters. nano = 10^-9

8. darkb0nebeauty

ok this wat i got = 1000000000000

9. Frostbite

wait.. how did you get that huge number?

10. darkb0nebeauty

i got t bye mulitplyn 10^-9*1000

11. Frostbite

I doubt that. Lets do it in the head: $10^{-9}*1000=10^{-9}*10^{3}=10^{-9+3}=10^{-6}$

12. darkb0nebeauty

oh ok so the answer is 10^-6

13. Frostbite

wait...

14. Frostbite

it was not 10^-9 but 10^-10

15. Frostbite

$10^{-10} m*1000=10^{-10} m *10^{3}=10^{-10+3} m=10^{-7} m$ $10^{-7} m * 10^{9} \frac{ nm }{ m }=100 nm$

16. darkb0nebeauty

so 100nm is that right

17. Frostbite

Yes 100 nano meters :)

18. Frostbite

I think. not 100% sure if the procedure is right... seems to esay for some reason.

19. darkb0nebeauty

ok so 100nm, can you help me with another one

20. Frostbite

Just post it then I might take a look :)

21. Frostbite

I ment as a question :)

22. darkb0nebeauty

Consider the sequence 2, 6, 18, 54…. Let n= the term number in the sequence. Let A (n) = the value of the nth term of the sequence. 4. What is the common ratio of the sequence? Common ratio: 5. Complete each statement. a. A (1) =2=2*3^? b. A (2) =6=2*3=2*3^? c. A (3) =18=2*3*3=2*3^? d. A (4) =54=2*3*3*3=2*3^? 6. What is the relationship between the exponent of the base 3 and the value of n? 7. Complete the statement: A (n) = 2*3^?

23. Frostbite

Hmmm I think you need to post this as a seperate question, not sure I fully understand the question.

24. darkb0nebeauty

Activity 2 Consider the sequence 2, 6, 18, 54…. Let n= the term number in the sequence. Let A (n) = the value of the nth term of the sequence. 4. What is the common ratio of the sequence? Common ratio: 5. Complete each statement. a. A (1) =2=2*3^? b. A (2) =6=2*3=2*3^? c. A (3) =18=2*3*3=2*3^? d. A (4) =54=2*3*3*3=2*3^?

25. Frostbite

I just ment i don't understand the way they put it... I'm not from the US so I have to translate the words back and forth, and when I do so I get something that don't make sence. All I can say is that you can discribe your function/seq as this: A(n)=2*3^n, n belongs to all whole positive numbers.

26. darkb0nebeauty

ok, is that is that all you get. @Frostbite wat bout you @aspenfields

27. aspenfields

im just thinking and trying to figure it out atm

28. darkb0nebeauty

haye ca you put that work back to the first one please...@Frostbite

29. tayluvsya

@skullpatrol

30. darkb0nebeauty

ok while we are waitin for that one can u help me with this other one...please!!!

31. tayluvsya

which one

32. darkb0nebeauty

A. What is the common ratio of the sequence 80, 20, 5, 5/4…? Common ratio: B. What are the next three terms in the sequence? Next three terms:

33. darkb0nebeauty

34. skullpatrol

Any ideas?

35. darkb0nebeauty

ok are you going tew help me on the first one or the next three term, but with the first one o idea and the second one i do i have 1 idea

36. skullpatrol

What number do you need to multiply by 80 to get 20?

37. darkb0nebeauty

you cant muliply anything by 80 to get 20 but 20*4 is 80

38. skullpatrol

How about $$\frac{1}{4}$$

39. darkb0nebeauty

oh so 80 tmes 1/4 is 20

40. skullpatrol

$$80*\frac{1}{4}=20$$

41. darkb0nebeauty

oh ok so 20*1/4=5

42. skullpatrol

Yes.

43. darkb0nebeauty

thanks so much ok so can you help me on the other one now.... the first one or do you want me to post it up there

44. darkb0nebeauty

wait can you help me on the next three terms

45. skullpatrol

Just keep multiplying by 1/4...

46. darkb0nebeauty

ok is the next term 5/16, then 5/64, then 5/256

47. darkb0nebeauty

is that right

48. darkb0nebeauty

are yall still there.@skullpatrol @tayluvsya

49. darkb0nebeauty

@skullpatrol

50. skullpatrol

Correct.

51. darkb0nebeauty

so i did it right. ok so can you help me on the first one

52. darkb0nebeauty

i really dont get so can you please help me

53. skullpatrol

What was the question?

54. darkb0nebeauty

Activity 2 Consider the sequence 2, 6, 18, 54…. Let n= the term number in the sequence. Let A (n) = the value of the nth term of the sequence. 4. What is the common ratio of the sequence? Common ratio: 5. Complete each statement. a. A (1) =2=2*3^? b. A (2) =6=2*3=2*3^? c. A (3) =18=2*3*3=2*3^? d. A (4) =54=2*3*3*3=2*3^?

55. skullpatrol

What do you have to multiply 2 by to get 6?

56. darkb0nebeauty

3

57. darkb0nebeauty

so all of them are three is that alright

58. skullpatrol

Just like multiplying by 1/4 each time.

59. darkb0nebeauty

ok that i dont get can you please help me i have to turn this in before 12:30

60. skullpatrol

To get the next term multiply by 3

61. darkb0nebeauty

so a. 6 b.18 c.54 d. 162 is that right

62. skullpatrol

Yes.

63. skullpatrol

The whole idea behind these type of questions is to answer: "what do I need to multiply by to get the next term"? and then continue using that number.

64. darkb0nebeauty

so what i got up there are those the right answers....

65. skullpatrol

Yes.

66. darkb0nebeauty

ok i have 3 more

67. darkb0nebeauty

actually it comes along with it, look back up with the one we just worked out and it says the common ratio, is the ratio times 1/4 or what

68. darkb0nebeauty

haye wat happened @skullpatrol