Understanding Newton's Contributions to Physics

What realization did Newton have when he saw an apple fall from a tree?

• The Earth's rotation causes the apple to fall.

• The apple falls due to its own weight, independent of other forces.

• The apple and Earth pull on each other with equal force.

What does the gravitational force between two objects depend on according to Newton?

• The color and size of the objects

• Only the mass of the larger object

• The mass of the objects and the square of the distance between them

What did Newton add to his gravitational equation to account for the small observable effects of gravity?

• A large constant to increase the force

• The variable 'G', a very small constant

• A variable representing the Earth's atmosphere

According to Kepler's second law, what remains constant as a planet orbits the Sun?

• The distance from the Sun

• The time it takes for a complete orbit

• The area swept out by the line from the planet to the Sun in a given time

How did Newton's law of universal gravitation help explain the orbits observed by Kepler?

• It showed that orbits are circular, not elliptical.

• It suggested that other forces besides gravity affected planetary orbits.

• It provided a mathematical basis for the gravitational forces involved in the orbits.