Question

Which of these time measurements is the smallest? A) 0.02 seconds. B) 0.02 teraseconds. C) 2,500 milliseconds. D) 25,000 nanoseconds

Answer 1

In order to answer the question, we convert the measurements given to a common base unit. For this case, we use seconds.

A)   0.02 seconds
B)   0.02 teraseconds x (10^12 s / 1 terasecond) = 2x10^10 seconds
C)   2,500 milliseconds x (1 s / 1000 ms) = 2.5 seconds
D)   25,000 nanoseconds x (1 x 10^-9 s / 1 nanosecond) = 2.5 x 10^-5 seconds

Therefore, among the choices listed above the correct answer is D.

Answer 2

To answer the question, convert all of these measurements to a common unit. I choose seconds as the basis.

(a)   0.02 seconds
(b)   0.02 teraseconds x (10^12 s / 1 terasecond) = 2x10^10 seconds
(c)   2,500 milliseconds x (1 s / 1000 ms) = 2.5 seconds
(d)   25,000 nanoseconds x (1 x 10^-9 s / 1 nanosecond) = 2.5 x 10^-5 seconds
The answer is letter D.