Solve the problem.
-Find v for the tip of the hour hand of a clock, if the hand is 7 cm long.
A) $42 \pi \mathrm { cm }$ per hour
B) $\frac { 7 \pi } { 12 } \mathrm {~cm}$ per hour
C) $\frac { 7 \pi } { 3 } \mathrm {~cm}$ per hour
D) $\frac { 7 \pi } { 6 } \mathrm {~cm}$ per hour

Question

Solve the problem.
-Find v for the tip of the hour hand of a clock, if the hand is 7 cm long. 
A) $42 \pi \mathrm { cm }$ per hour
B) $\frac { 7 \pi } { 12 } \mathrm {~cm}$ per hour
C) $\frac { 7 \pi } { 3 } \mathrm {~cm}$ per hour
D) $\frac { 7 \pi } { 6 } \mathrm {~cm}$ per hour

Quizplus · Accepted Answer

The hour hand completes one full circle (circumference $2 \pi r$) in 12 hours. With $r = 7$ cm, the circumference is $14 \pi$ cm. Thus, the speed is $\frac{14 \pi}{12} = \frac{7 \pi}{6}$ cm per hour.

Solve the Problem 42πcm42 \pi \mathrm { cm }42πcm Per Hour B)

Solve the Problem $42 \pi \mathrm { cm }$ Per Hour
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