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3 years ago

8

A 16 g piece of Styrofoam carries a net charge of -8.6 µC and floats above the center of a large horizontal sheet of plastic tha

t has a uniform charge density on its surface. What is the charge per unit area on the plastic sheet?

1 answer:

PilotLPTM [1.2K]3 years ago

8 0

Answer:

the charge per unit area on the plastic sheet is - 3.23 x 10⁻⁷ C/m²

Explanation:

given information:

styrofoam mass, m = 16 g = 0.016 kg

net charge, q = - 8.6 μC

to calculate the charge per unit area on the plastic sheet, we can use the following equation:

$F_{e} = mg$

where

$F_{e} =$ the force between the electric field

m = mass

g = gravitational force

$F_{e} =qE$

where

q = charge

E = electric field

and

E = σ/2ε₀

where

ε₀ = permitivity

thus

$F_{e} =qE$

mg = qσ/2ε₀

σ = (2mg ε₀)/q

= 2 (0.016) (9.8) (8.85 x 10⁻¹²)/( - 8.6 x 10⁻⁶)

= - 3.23 x 10⁻⁷ C/m²

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Answer:

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Explanation:

$\Delta x$ = Uncertainty in position = 1.9 m

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Murrr4er [49]

<h2>Answer: 502.08 J</h2>

Explanation:

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$Q=m.C.\Delta T$ (1)

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