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A projectile is launched from level ground with an initial velocity v at an angle θ to the horizontal. The range of the projectile is initially d when the gravitational acceleration is g. If, at the peak of its motion, the projectile enters a zone where the effective gravitational acceleration becomes g' = g/0.81, the new range becomes d'. What is the value of n?

1. n = 0.8
2. n = 0.95
3. n = 1.0
4. n = 1.2

Correct answer: n = 0.95

Solution

The value of n is determined by the ratio of the ranges of the projectile under different gravitational accelerations, and using the equations of motion for the projectile yields n = 0.95.

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