16. Olympic ice skaters are able to spin at about 5 rev/s.

Physics

1 answer:

Wittaler [7]3 years ago

5 0

Answer:

a) w = 31.4 rad / s, b) a = 118.4 m / s²

Explanation:

a) let's reduce to the SI system

w = 5 rev / s (2pi rad / 1 rev)

w = 31.4 rad / s

b) the expression for the centripetal acceleration is

a = v² / r

linear and angular variables are related

v = w r

we substitute

a = w² r

a = 31.4² 0.120

a = 118.4 m / s²

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JulsSmile [24]

Answer:

$\mu =0.75$

Explanation:

<u>Frictional Force </u>

When the car is moving along the curve, it receives a force that tries to take it from the road. It's called centripetal force and the formula to compute it is:

$F_c=m.a_c$

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$F_r=\mu N$