Q2. Express the followings measurements using prefixes.

a. 27.5 x 10-10 m        b. 0.00023 x 10-2 s

Ans:

a. 27.5 x 10-10 m

We will convert the number first to scientific notation. For this purpose, we have to move the decimal to bring it in between 2 and 7.
27.5 x 10-10 m = 2.75 x 10+1 x 10-10 m = 2.75 x 10-9 m
As 10-9 = n,  is equal to nano, so:  2.75 nm

27.5 x 10-10 m = 2.75 nm

b. 0.00023 x 10-2 s

We will convert the number first to scientific notation. For this purpose, we have to move the decimal to bring it in between 2 and 3.
0.00023 x 10–2 s = 2.3 x 10-4 x 10–2 s = 2.3 x 10-6 s
As 10-6 = μ  is equal to micro, so: 2.3 μm

0.00023 x 10–2 m = 2.3 μm

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