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2 years ago

5

A bicycle has wheels of 0.8 m diameter. The bicyclist accelerates from rest with constant acceleration to 22 km/h in 11.6 s. Wha

t is the angular acceleration of the wheels?

1 answer:

larisa [96]2 years ago

7 0

Answer:

α = 1.32 rad/s²

Explanation:

given,

diameter of the bicycle = 0.8 m

radius of the bicycle = 0.4 m

initial speed of the bicyclist,u = 0 m/s

final speed of the bicyclist,v = 22 Km/h = 22 x 0.278

= 6.12 m/s

time,t = 11.6 s

acceleration = $\dfrac{v-u}{t}$

= $\dfrac{6.12-0}{11.6}$

=0.53 m/s²

we know,

a = α r

$\alpha=\dfrac{a}{r}$

$\alpha=\dfrac{0.53}{0.4}$

α = 1.32 rad/s²

the angular acceleration of the wheels is equal to α = 1.32 rad/s²

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