Consult your doctor if: 1  Your headache symptoms occur more than 15 days a month or require frequent over-the-counter pain medicine. 2  You have a severe headache, and over-the-counter pain medicine doesn't help. 3  You miss school or work because of frequent headaches or the headaches interfere with your daily life. 4  Definition. Causes.
Newton's law of gravitation. (nt'nz) The principle that expresses the force of gravitational attraction between two bodies as a function of their mass and their distance.
But Newton's law of universal gravitation extends gravity beyond earth. Newton's law of universal gravitation is about the universality of gravity. Newton's place in the Gravity Hall of Fame is not due to his discovery of gravity, but rather due to his discovery that gravitation is universal. ALL objects attract each other with a force of gravitational attraction. Gravity is universal.