Question

(II) Time intervals measured with a stopwatch typically have an uncertainty of about 0.2 s, due to human reaction time at the start and stop moments.What is the percent uncertainty of a hand-timed measurement of (a) 5.5 s, (b) 55 s, (c) 5.5 min?

Answer 1

Answer:

(a) 36.36%

(b) 0.36%

(c) 0.06%

Step-by-step explanation:

Given that the time intervals measured with a stopwatch have an uncertainty of about 0.2 s.

We want to know what is the percent uncertainty of a hand-timed measurement of:

(a) 5.5 s

Percentage = (0.2/5.5) × 100

≈ 36.36%

(b) 55 s

Percentage = (0.2/55)×100

≈ 0.36%

(c) 5.5 min

5.5 min = 5.5 × 60 s

= 330 s

Percentage = (0.2/330)×100

≈ 0.06%