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3 years ago

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Anissa slides down a playground slide sloped at 25o. The coefficient of kinetic friction between Anissa and the slide is 0.15. I

f Anissa’s mass is 55 kg, how fast is she going 2.0 s after starting from rest?

1 answer:

Keith_Richards [23]3 years ago

4 0

Answer:5.62 m/s

Explanation:

Given

Inclination $\theta =25^{\circ}$

Coefficient of kinetic Friction $\mu _k=0.15$

mass of Anissa's $m=55 kg$

time interval $t=2 s$

acceleration of the system

$a=g\sin \theta -\mu _kg\cos \theta$

$a=9.8\sin (25)-0.15\cdot 9.8\cos (25)$

$a=4.14-1.33=2.81 m/s^2$

$v=u+at$

where v=Final Velocity

u=Initial Velocity

a=acceleration of system

t=time

$v=0+2.81\times 2$

$v=5.62 m/s$

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