A parallel-plate capacitor is constructed of two horizontal 16.8-cm-diameter circular plates. A 1.8 g plastic bead, with a charg
1 answer:
Answer:
Explanation:
Given that:
diameter of the circular plates = 16.8 cm
mass of the plastic bead = 1.8 g
charge q = -4.4 nC
From above, the area of the circular plates is:
Area = 0.022 m²
Thus, as the plastic beads glide between the two plates of the capacitor, there exists a weight acting downwards while the weight is balanced by the force of the plates acting upwards.
Hence, this can be achieved only when the upper plate is positively charged.
b)
Recall that
Force (F) = qE
where;
F = mg
mg = qE
E = 4.0 × 10⁶ N/C
From the electric field;
Q = 7.788 × 10⁻⁷ C
Q = 779 nC
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Explanation:
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