Which of the following best defines the order of magnitude of a physical quantity…

PHYSICS · Single correct · A Level · Physics · Measurements and their errors · Measurements and their errors

Problem

Which of the following best defines the order of magnitude of a physical quantity written in scientific notation? (a) The coefficient

a

in the expression

a\times10^{n}

where

1\le a<10

. (b) The power of

10

obtained by simply counting the digits before the decimal point, without any rounding of the coefficient. (c) The exponent of

10

that results after rounding the coefficient so that it becomes

1

when

1\le a<5

and

10

when

5\le a<10

. (d) The total number of significant figures present when the quantity is written in scientific notation.