BrainMan said:Homework Statement
Two identical rocks of mass 2 kg drift through space far from any planet or star. If they pass one another at a separation of 30 cm, what is the magnitude of the gravitational force of one rock on the other at this instant.
Homework Equations
F = G (m1m2/r2)
The Attempt at a Solution
(4/.32)(6.673 x 10-11) = F
(4/.09)(6.673 x 10-11 = F
44.444444444444(6.673 x 10-11 = F
F = 3.804 x 10-8 N
the actual answer is F = 2.96 x 103 N
OK I see my mistake and the answer I put was a typo it is actually 2.96 x 10-9 Ngneill said:The "actual answer" is not correct, but it is the order of magnitude that is wrong not the mantissa of the number. Perhaps you misquoted the power of ten?
Regarding your solution attempt, your formula is fine but your math is not right. Recheck your calculation.
Newton's law of gravity is a fundamental law of physics that describes the force of gravitational attraction between two objects. It states that the force of gravity between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Newton's law of gravity applies to all objects in the universe, from the motion of planets and galaxies to the fall of an apple from a tree. It is also used in engineering and space exploration to calculate the trajectories of objects in motion.
The equation for Newton's law of gravity is F = G * (m1 * m2) / r2, where F is the force of gravity, G is the universal gravitational constant, m1 and m2 are the masses of the two objects, and r is the distance between them.
According to Newton's law of gravity, the force of gravity decreases as the distance between two objects increases. This means that the farther apart two objects are, the weaker the force of gravity between them.
Newton's law of gravity is a simplified version of gravity that works well for most everyday situations. However, Einstein's theory of general relativity is a more accurate and comprehensive theory that explains gravity as the curvature of spacetime caused by the presence of mass and energy.