[+fullrep] Science Help [light years/light seconds/scientific notation]

[Maki]

"If 9.46x10^12 km = 1 ly, how many kilometers are there in 1 ls?"

Use GRASS method, and explain the reasoning behind your steps so I can understand it; basically you're teaching me this because my teacher made some dumbass in our class teach this to us.

[aznboy1997]

I will be honest with you, I'm not exactly sure about the "GRASS" method you are talking about, but I'll try to explain it as best as I can.

Since you are going from light years to light seconds, you will divide by 365 to obtain the length in km of one light-day, by 24 to obtain the length in km of one light-hour, and by 3600 to obtain the length in km of one light-second.

Therefore, 9.46*10^12/365/24/3600 = 3.00*10^5 km per light-second.

Hope it helps! :D

[Maki]

OHHHHHHHHH I get it!

Thanks!

[wrath]

I will be honest with you, I'm not exactly sure about the "GRASS" method you are talking about, but I'll try to explain it as best as I can.

Since you are going from light years to light seconds, you will divide by 365 to obtain the length in km of one light-day, by 24 to obtain the length in km of one light-hour, and by 3600 to obtain the length in km of one light-second.

Therefore, 9.46*10^12/365/24/3600 = 3.00*10^5 km per light-second.

Hope it helps! :D

Leave it to an Aznboy right? :P I was looking at it, but I was always horrible with conversions. Thanks for explanation though, I was also curious.

[Maki]

I will be honest with you, I'm not exactly sure about the "GRASS" method you are talking about, but I'll try to explain it as best as I can.

Since you are going from light years to light seconds, you will divide by 365 to obtain the length in km of one light-day, by 24 to obtain the length in km of one light-hour, and by 3600 to obtain the length in km of one light-second.

Therefore, 9.46*10^12/365/24/3600 = 3.00*10^5 km per light-second.

Hope it helps! :D

;____; I get 299,974.6322

[Bettser]

;____; I get 299,974.6322

He rounded it up and put it into scientific notation.

[Maki]

He rounded it up and put it into scientific notation.

I know I can look up how to turn stuff into scientific notation...but explain it to me?

[Bettser]

I know I can look up how to turn stuff into scientific notation...but explain it to me?

You know what rounding is so I dont need to explain that :P but for scientific notation:

You got 299,974.6322 as your answer. It looks quite tedious and simplified it looks like:

2.999746322 x10^5

If you multiply those numbers^, you get your original answer. Teachers normally want it to two decimal points so:

2.99x10^5 (Same answer, just more simplified)

Teachers also usually want the answer rounded to which arrives you at aznboy's answer.

3.00x10^5

[Maki]

You know what rounding is so I dont need to explain that :P but for scientific notation:

You got 299,974.6322 as your answer. It looks quite tedious and simplified it looks like:

2.999746322 x10^5

If you multiply those numbers^, you get your original answer. Teachers normally want it to two decimal points so:

2.99x10^5 (Same answer, just more simplified)

Teachers also usually want the answer rounded to which arrives you at aznboy's answer.

3.00x10^5

Wait, where did you get the exponent '5' from?

[Bettser]

Wait, where did you get the exponent '5' from?

By moving the decimal point :P

Example:
2.999746322 x10^5
29.99746322 x10^4
299.9746322 x10^3
2999.746322 x10^2

Are all the same as
299,974.6322

:P

[Maki]

By moving the decimal point :P

Example:
2.999746322 x10^5
29.99746322 x10^4
299.9746322 x10^3
2999.746322 x10^2

Are all the same as
299,974.6322

:P

Waittt though idgi :(
I got 299,974.6322
If I move the decimal 5 times to the left I get
29.99746322x10^5

[Mod]

What Bettser said.

Most high school problem sets advise you to answer to 2 decimal places (x.xx).
But to be more precise, look at the highest sig dig (aka sig figs) given in any # of the original problem. For instance, if a question throws out numbers like 2.34, 1.222, and 8.787777 in it, answer to 2 decimal places (2.34).

...and never use exponent "10^1" in scientific notation, because that's just "10". You'll likely get docked marks if you do, minimum in scientific notation is always "10^2", onwards.

---------- Post added at 05:28 PM ---------- Previous post was at 05:26 PM ----------


Waittt though idgi :(
I got 299,974.6322
If I move the decimal 5 times to the left I get
29.99746322x10^5

Are you following BEDMAS? Exponents first.

10^5 = 100,000

2.99 * 100,000 = 299,000

aka 2.99 * 10^5

---

Never multiply your value by '10', then exponent it...remember BEDMAS.

[Bettser]

Waittt though idgi :(
I got 299,974.6322
If I move the decimal 5 times to the left I get
29.99746322x10^5

:P

2.999746322 x10^5
29.99746322 x10^4
299.9746322 x10^3
2999.746322 x10^2
29997.46322 x10
299974.46322