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2 months ago

A 1 mg ball carrying a charge of 2 x 10-8 C hangs from a

Physics

1 answer:

Keith_Richards [3.2K]2 months ago

7 0

Answer:

σ = 0.255*10^-3 C/m²

Explanation:

The electric field intensity generated by the plate is calculated as σ/ε₀, where σ denotes the surface charge density of the plate.

In a state of equilibrium,

The upward force equals the downward force

Tcosθ = mg ----(1)

Assuming that the forward force equals the backward force, then

Tsinθ = σq/ε₀

[ ∵ F = qE, ∴ F = qσ/ε₀ ] -----(2)

Dividing equation (2) by equation (1)

Tsinθ/Tcosθ = qσ/ε₀mg

This leads to Tanθ = qσ/ε₀mg

Consequently, σ = ε₀mg tanθ/q

Now, substituting in the values gives us

σ = (8.85*10^-12 * 1 * tan 30) / (2*10^-8)

σ = (8.85*10^-12 * 0.5774) / (2*10^-8)

σ = 5.11*10^-12 / (2*10^-8)

σ = 0.255*10^-3 C/m²

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3 months ago

A conducting sphere 45 cm in diameter carries an excess of charge, and no other charges are present. You measure the potential o

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Explanation:

According to the question, we are informed that

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$V = \frac{k * Q }{r }$

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2 months ago

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A is the area over which heat transfer takes place
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Upon examining the thermal conductivity values for each metal, we observe:
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- Gold: 314 W/(mK)
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3 months ago