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Capacitors. Two large parallel sheets of charge are separated by a distance d , small compared to the size of the sheets . The distance d is small enough that the sheets can be treated as if they were infinite in extent . .
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Two large parallel sheets of charge are separated by a distance d , small compared to the size of the sheets. The distance d is small enough that the sheets can be treated as if they were infinite in extent. Where do you expect the E field to point at the position A? • It should point to the left. • It should be essentially 0. • It should point to the right. A C B NEXUS/Physics Clicker Questions
Two large parallel sheets of charge are separated by a distance d , small compared to the size of the sheets. The distance d is small enough that the sheets can be treated as if they were infinite in extent. Where do you expect the E field to point at the position B? • It should point to the left. • It should be essentially 0. • It should point to the right. A C B NEXUS/Physics Clicker Questions
Two large parallel sheets of charge are separated by a distance d , small compared to the size of the sheets. The distance d is small enough that the sheets can be treated as if they were infinite in extent. Where do you expect the E field to point at the position C? • It should point to the left. • It should be essentially 0. • It should point to the right. A C B NEXUS/Physics Clicker Questions
If the sheets can be treated as if they were infinitely large, which of the following graphs might serve as a graph of the x-component of the electric field as a function of the coordinate x along the dotted line? NEXUS/Physics Clicker Questions
If the sheets can be treated as if they were infinitely large, which of the following graphs might serve as a graph of the electric potential as a function of the coordinate x along the dotted line? NEXUS/Physics Clicker Questions
E + + + + + + + – – – – – – – V 0 What would happen to the voltage if you first disconnected the battery and then pulled the plates further apart? • The potential difference would increase. • The potential difference would decrease. • The potential difference would stay the same. NEXUS/Physics Clicker Questions
E + + + + + + + – – – – – – – V 0 What would happen to the voltage if you stayed connected to the battery and then pulled the plates further apart? • The potential difference would increase. • The potential difference would decrease. • The potential difference would stay the same. NEXUS/Physics Clicker Questions
E + + + + + + + – – – – – – – V 0 What would happen to the voltage if you stayed connected to the battery and then pulled the plates further apart? • The charge on each platewould increase. • The charge on each platewould decrease. • The charge on each platewould stay the same. NEXUS/Physics Clicker Questions
Cap #1 is charged by connecting it to a battery. Cap #2 is not charged.C#1 is disconnected from the battery and connected to C#2. How does the magnitude of the E field in C#1 change? • Stays the same • Bigger by ~X2 • Bigger but not by ~X2 • Smaller by ~X2 • Smaller but not by ~X2 • Can’t tell NEXUS/Physics Clicker Questions
Three capacitors 1, 2, 3 are connected to identical batteries so they each have the same ΔV. Their plate areas and separations are as follows: A2 = 2 A1 = 2 A3; d1 = d2 = 2d3.How do the E fields inside them rank? • E2= E3> E1 • E3> E1= E2 • E2> E1> E3 • E2> E1= E3 • E1= E2> E3 • E1= E2= E3 • Other NEXUS/Physics Clicker Questions
Three capacitors 1, 2, 3 are connected to identical batteries so they each have the same ΔV. Their plate areas and separations are as follows: A2 = 2 A1 = 2 A3; d1 = d2 = 2d3.How do the net charges on them rank? • Q2 = Q3 > Q1 • Q3 > Q1 = Q2 • Q2 > Q1 > Q3 • Q2 > Q1 = Q3 • Q1 = Q2 > Q3 • Q1 = Q2 = Q3 • Other NEXUS/Physics Clicker Questions
Three capacitors 1, 2, 3 are connected to identical batteries so they each have the same ΔV. Their plate areas and separations are as follows: A2 = 2 A1 = 2 A3; d1 = d2 = 2d3.How do the positive charges on their top plate rank? • Q2 = Q3 > Q1 • Q3 > Q1 = Q2 • Q2 > Q1 > Q3 • Q2 > Q1 = Q3 • Q1 = Q2 > Q3 • Q1 = Q2 = Q3 • Other NEXUS/Physics Clicker Questions
Three capacitors 1, 2, 3 are connected to identical batteries so they each have the same ΔV. Their plate areas and separations are as follows: A2 = 2 A1 = 2 A3; d1 = d2 = 2d3.How do the voltage drops across their plates rank? • ΔV2 = ΔV3 > ΔV1 • ΔV3 > ΔV1 = ΔV2 • ΔV2 > ΔV1 > ΔV3 • ΔV2 > ΔV1 = ΔV3 • ΔV1 = ΔV2 > ΔV3 • ΔV1 = ΔV2 = ΔV3 • Other NEXUS/Physics Clicker Questions
Suppose we: • Close A for a few seconds • Open A • Close B • What happens to the bulb? • It stays off. • It stays on after you close A • It stays on after you close B • It flashes when you close A • It flashes when you open A • It flashes when you close B B NEXUS/Physics Clicker Questions A
Suppose the capacitor is connected to the battery. The plates remain connected and an insulating slab of dielectric constant 𝜅 ( > 1) is slid between the plates. What happens to the electrical energy stored in the capacitor as a result of inserting the insulating slab? • The stored electrical energy increases. • The stored electrical energy remains the same. • The stored electrical energy decreases. NEXUS/Physics Clicker Questions