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A vertical electric field of magnitude 4.9 × 10 5 N/C just prevents a water droplet of a mass 0.1 g from falling. The value charge on the droplet will be (Given g = 9.8 m/s 2 )

1. 1.6 × 10 –9 C
2. 2.0 × 10 –9 C
3. 3.2 × 10 –9 C
4. 0.5 × 10 –9 C

Correct answer: 2.0 × 10 –9 C

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