Question

The age of the universe is thought to be about 14 billion years. Assuming two significant figures, write this in powers of ten in (a) years, (b) seconds.

Answer 1

14 billion years!! O.O That's pretty old.
So 14,billion is also 14,000,000,000 right?
Now to write it in powers in the standard form we put the decimal point at 1.4 and just count the number of points till the end!
So it can also be written as...
1.4x10^10 years!!
Getting me? :)

Answer 2

Yes but I thought you had to multiply 60 because that is how much second are in a minutes to something I don't know I'm just very cunfused. I get what you're saying though.

Answer 3

Alrighty then now we move ahead for seconds! :D

Answer 4

So in seconds you need to know something known as a unit factor!
A unit factor is basically something whose magnitude in conversion results in ONE.
For example:
24 hours/1 day is a unit factor or
1 hour/60 minutes is also a unit factor.
So to convert years to seconds we use the UNIT FACTOR METHOD! :D
So we multiply 14bil years * 365 days/ 1 year * 24hours/1 day * 60 minutes/1 hour * 60 seconds/1 minute..
I SUGGEST YOU WRITE THIS ON PAPER.
SO WHAT YOU WILL SEE IS THAT ALL THE UNITS GET CUT BUT SECONDS ARE LEFT.
AND TO GET THE VALUE IN SECONDS JUST MULTIPLY THE NUMERATOR VALUES.
AND THEN WRITE IT IN STANDARD FORM LIKE IN YEARS!!
THAT IS IT.
Getting me? :)

Answer 5

YES!!! That actually made sence thank you¡!¡!!!!!!

Answer 6

:)