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4 years ago

A regulation basketball has a 22 cm di-

Physics

1 answer:

Solnce55 [7]4 years ago

4 0

Answer:

0.70 s

Explanation:

Potential energy = kinetic energy + rotational energy

mgh = ½ mv² + ½ Iω²

For a thin spherical shell, I = ⅔ mr².

mgh = ½ mv² + ½ (⅔ mr²) ω²

mgh = ½ mv² + ⅓ mr²ω²

For rolling without slipping, v = ωr.

mgh = ½ mv² + ⅓ mv²

mgh = ⅚ mv²

gh = ⅚ v²

v = √(1.2gh)

v = √(1.2 × 9.81 m/s² × 1.1 m sin 49.0°)

v = 3.13 m/s

The acceleration down the incline is constant, so given:

Δx = 1.1 m

v₀ = 0 m/s

v = 3.13 m/s

Find: t

Δx = ½ (v + v₀) t

t = 2Δx / (v + v₀)

t = 2 (1.1 m) / (3.13 m/s + 0 m/s)

t = 0.704 s

Rounding to two significant figures, it takes 0.70 seconds.

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sweet-ann [11.9K]

a) The magnetic field created by a current-carrying wire is proportional to the current:

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Let's focus on wire 1.

Since wire 2's current is doubled, wire 2 produces a magnetic field twice as strong as before.

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3 years ago

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lbvjy [14]

Answer:

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Explanation:

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3 years ago