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The second hand on a watch is 3.0 cm long and rotates smoothly. What is the speed of the tip of the hand?

User Vookimedlo
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1 Answer

4 votes

Answer:

v = 0.00314 m/s

Step-by-step explanation:

First we need to find the angular velocity of the second hand of the clock:

ω = θ/t

where,

ω = angular velocity = ?

θ = angular displacement

t = time taken

For 1 complete revolution:

θ = 2π radians

t = 60 s

Therefore,

ω = 2π rad/60 s

ω = 0.104 rad/s

Now, for the speed of the tip of second hand of watch:

v = rω

where,

v = speed of the tip = ?

r = radius = 3 cm = 0.03 m

Therefore,

v = (0.03 m)(0.104 rad/s)

v = 0.00314 m/s

User Tukusejssirs
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