Question

IBM has a computer it calls the Blue Gene/L that can do 136.8 teracalculations per second. How many calculations can it do in a microsecond?

The answer has to be in four significant digits.....

Answer 1

Just do a proportion

Answer 2

well i now micro is 10^-6..... and tera is 10^12, but Im not sure what to multiply 136.8 by

Answer 3

we are given (136.8) (10^12) calculations / second .

we also know that 1 second = 10^6 microseconds .

thus
(136.8) (10^12) calculations / second * (1second / 10^6 microseconds)

= (136.8) (10^6) calculations / microsecond
or
136.8 mega-calculations / microsecond .

Answer 4

but i don't want mega...... i need microseconds

Answer 5

My bad, 0.1368 TeraCalculations/microsecond

Answer 6

136.8 tera calculations / 1 second = 136.8 * 10^12 calculations / second
in 1 microsecond, it does 136.8 * 10^12 calculations / second * 1 second / 10^6 microseconds = 136.8 * 10^6 calculations / microsecond

Answer 7

im not following

Answer 8

draw?

Answer 9

What whpalmer4 said was not in 4 digits, his answer was 136800000

Answer 10

well i dont understand how u or him got those answers

Answer 11

136.8 *10^6 is 4 significant figures.

Answer 12

I did not write 136800000 (which is also 4 significant figures)

Answer 13

Right, my mistake, now i am completely confused.

Answer 14

hmm, confusing everyone is not my goal :-)

Answer 15

sooo... im still confused on how you got, 136800000

Answer 16

First, let's figure out a number for 136.8 tera calculations.

136.8 tera = 136.8 * 10^12 because tera means 10^12

Agreed so far?

Answer 17

agree

Answer 18

Okay, it does 136.8 tera calculations per second, so that means

136.8 *10^12 calculations / second

agreed?

Answer 19

yes

Answer 20

okay, now we're just going to apply a conversion factor to change seconds to microseconds.

136.8*10^12 calc/sec * 1 sec / 10^6 microsecond = 136.8 * 10^6 calc/microsecond

Answer 21

okay, so should i keep it like that or make it 136800000

Answer 22

in science problems you rarely go wrong by staying with scientific notation, in my experience.

Answer 23

but this is on mastering physics website..... so its on the computer, i guess i will have to see :) thanks

Answer 24

well, as always, you have to adapt to whatever unreasonable demands are placed on you, until you don't :-)

Answer 25

but in general, scientific notation is much more convenient when doing (wait for it) science. for example, I helped with a problem last night where the goal was to find the frequency of some violet light. I think you'll agree that 5.77 * 10^14 Hz or 577 THz is a much more convenient answer than 577000000000000 Hz :-)

Answer 26

or substitution

Answer 27

ooh i had mastering physics :D I rocked at that lol.

Answer 28

you can also use dimensional analisys.

Answer 29

hopefully it works and cancels out