Three timer Consider three vacuum filled parallel plate capacitors each with

Three timer consider three vacuum filled parallel

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31.Three timer.Consider three vacuum-filled parallel-plate capacitors, each with chargeQ,whose properties are listed in the table shown. Which of the following is the correct rela-tionship among the energies stored in each capacitor?CapacitorAreaSeparation DistanceX2A3dY4Ad/5ZA/52d A.UX< UY< UZB.UZ< UY< UXC.UZ< UX< UYD.UY< UX< UZSolution:The capacitance of the parallel-plate capacitor isC=ε0Adand the energy stored in the capacitor isU=12Q2C=dQ22ε0ATherefore, the energy stored in each capacitor isUCapacitor X32dQ22ε0ACapacitor Y120dQ22ε0ACapacitor Z10dQ22ε0AA – 17
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Sample Exam Second Semester, AY 2016–2017 Physics 72 32.Kwatro Kantos.What happens to the energy density inside a vacuum-filled parallel-platecapacitor if the electric field magnitude between the plates is increased by a factor of4? 33.Capacitance.A spherical vacuum-filled capacitor with inner and outer radii ofRand2R,respectively, has a capacitance ofC. If the outer radius is increased to3R, what will be thenew capacitance?
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Sample Exam Second Semester, AY 2016–2017 Physics 72 35.Can you handle my drift?A current is travelling along a wire.The cross-sectionalarea of the wire suddenly increases by15%. If the current and the free-electron densityare maintained, what is the new drift velocity of the electrons in terms of the initial driftvelocity~vd?
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