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On a stopwatch, the tip of the second hand moves 2 cm in 15 seconds

How long is the second hand (to the nearest tenth)?

12.6 cm
1.3 cm
6.3 cm
30.0 cm

User Sixthpoint
by
6.6k points

2 Answers

5 votes

Answer:

B) 1.3 cm

Explanation:

User Yarbelk
by
7.1k points
0 votes
The given 2 cm is the length of the arc that the second hand had traveled for 15 seconds. Since the second hand completes a whole revolution in 60 seconds, it traveled approximately 1/4 of its circumference for 15 seconds. The length of the second hand is the radius of the circle.
2 cm = (1/4) x 2π x (L)
Solving for L gives an answer of 1.273 cm. Thus, the answer is the second choice, 1.3 cm.
User Dpwe
by
6.2k points
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