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Fields and their consequences (A-level only)

Fields and their consequences (A-level only)

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Question 126

A backup power system uses a 25 μF25\ \mu\text{F}25 μF capacitor to keep a memory chip active during a power glitch. When the power fails, the capacitor discharges through a resistor of resistance 120 kΩ120\text{ k}\Omega120 kΩ. What fraction of the capacitor's original charge remains after 4.5 s?

A

0.350.350.35

B

0.220.220.22

C

0.510.510.51

D

0.780.780.78

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Fields and their consequences (A-level only) Questions

  1. A Level
  2. /Physics
  3. /Fields and their consequences (A-level only)

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