Universal Gravitation

Problem #75

Tags: physics

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In most physics problems dealing with simple trajectories, we assume that the acceleration due to gravity is constant. For most familiar situations this is a reasonable assumption, it does not hold true in all situations.

In reality, all objects attract all other objects with gravitational force. The strength of this attractive force increases as the masses of the objects increases, and also as the distance between the two object decreases. To calculate the exact force of gravity between two objects, we can use the following equation, known as Isaac Newton's Law of Universal Gravitation:

$$ \huge F_{g} = \frac{G M m}{r^{2}} $$

Where

Problem Statement

Two planets A and B exist in a faraway corner of outer space, such that that the only forces acting upon them is the gravitational attractive force between each other. The two planets have masses mA and mB, with radii rA and rB, have their centers of mass in the exact center of each planet, and those centers are initially separated by the distance r0. Initially at t = 0 both planets are not moving relative to each other, immediately after which they will begin to move under the force of gravitational attraction.

How many hours after t = 0 will it take before the two planets collide?

Input Data
First line is Q, the quantity of testcases.
Q lines will then following, holding one testcase each in the format r0 rA rB mA mB.

Answer
Should consist of Q space-separated values, being how many hours before the planets collide in each testcase.
Round each answer to the nearest integer.

Example

input data:
2
10 1 2 3 4 
123456 12 34 56 78

answer:
264 141443309
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