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2 years ago

A trained sea lion slides from rest down a long

Physics

1 answer:

andrey2020 [161]2 years ago

5 0

Answer:

1.5 m/s²

Explanation:

Draw a free body diagram. There are three forces acting on the sea lion: gravity pulling down, normal force perpendicular to the ramp, and friction parallel to the ramp.

Sum of the forces perpendicular to the incline:

∑F = ma

N − mg cos θ = 0

N = mg cos θ

Sum of the forces parallel to the incline:

∑F = ma

mg sin θ − Nμ = ma

Substitute for N:

mg sin θ − (mg cos θ) μ = ma

g sin θ − g cos θ μ = a

a = g (sin θ − μ cos θ)

Given θ = 23° and μ = 0.26:

a = 9.8 (sin 23 − 0.26 cos 23)

a = 1.48

Rounded to two significant figures, the sea lion accelerates at 1.5 m/s².

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2 years ago

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3 years ago

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