A Small Styrofoam Ball of Mass $0.120 \mathrm {~g}$ Is Placed in an Electric Field Of

question 77

Multiple Choice

A small styrofoam ball of mass $0.120 \mathrm {~g}$ is placed in an electric field of $6000 \mathrm {~N} / \mathrm { C }$ pointing downward. What excess charge must be placed on the ball for it to remain suspended in the field?

• A) \(- 57.2 \mathrm { nC }\)
• B) \(- 18.0 \mathrm { nC }\)
• C) \(- 196 \mathrm { nC }\)
• D) \(- 125 \mathrm { nC }\)
• E) \(- 16.0 \mathrm { nC }\)

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Definitions:

Binomial Random Variable

A type of random variable that takes on a fixed number of possible outcomes, with each outcome having a constant probability of occurrence in each independent trial.

Normal Curve

A symmetric, bell-shaped curve representing the distribution of a set of data where most occurrences take place near the mean and probabilities for values taper off equally on both sides.

Continuity Correction

An adjustment made when approximating a discrete distribution with a continuous distribution.

Normal Approximation

A method of estimating the distribution of a sample statistic using the normal distribution, often applied when the sample size is large.