Suppose one night the radius of the earth doubled but its mass stayed the same. What would be an approximate new value for the free-fall acceleration at the surface of the earth? A. 2.5m/s22.5m/s 2
B. 5.0m/s25.0m/s 2
C. 10m/s210m/s 2
D. 20m/s220m/s 2

The free-fall acceleration at the surface of the new earth is , letter A.

Explanation:

Applying the equivalence principle we have:

Gravitational Force:

Newton's second law

Matching both equations, we have:

Where:

M is the mass of the earth

R is the radius of this new earth. In this case double of the earth

G is the gravitational constant

Therefore, the free-fall acceleration at the surface of the new earth is , letter A.

I hope it helps you!

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heat the gas and measure the pressure