The radius of the earth is R.At what distance above the earth's surface will the free-fall acceleration be 4.9 m/s²? A)0.41 R B)0.50 R C)1.00 R D)1.41 R E)0.25 R

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Quizplus · Accepted Answer

The free-fall acceleration at a distance r from the center of the Earth is given by g' = GM/r^2, where G is the gravitational constant and M is the mass of the Earth. At the surface of the Earth, r = R and g' = g = 9.8 m/s^2. If g' = 4.9 m/s^2, then r = sqrt(GM/g') = sqrt(GM/4.9) = 1.41R. Therefore, the distance above the Earth's surface is 1.41R - R = 0.41R.

The Radius of the Earth Is R