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You launch a rocket out of earth's atmosphere. As the rocket moves out of the atmosphere and into deep space, the gravitational constant g decreases and approaches 0, and the gravitational potential energy of the rocket:
A. also decreases and approaches 0
B. continually increases
C. remains constant
D. increases at first, and then decreases and approaches 0.
The answer is B.
Why isn't it D? As the rocket ascends within the atmosphere, its PE increases according to PE = mgh. Then, as g starts to decrease and approach 0, PE decreases and approaches 0, again according to PE = mgh.
How can PE continually increase if g is continually decreasing?
A. also decreases and approaches 0
B. continually increases
C. remains constant
D. increases at first, and then decreases and approaches 0.
The answer is B.
Why isn't it D? As the rocket ascends within the atmosphere, its PE increases according to PE = mgh. Then, as g starts to decrease and approach 0, PE decreases and approaches 0, again according to PE = mgh.
How can PE continually increase if g is continually decreasing?