Newton's Contribution to Gravity

What was one of Isaac Newton's major contributions to physics besides his laws of motion?

• Understanding of gravity

• Quantum mechanics

• Thermodynamics

• Theory of relativity

What realization did Newton have when an apple fell from a tree?

• Gravity is a force that acts at a distance

• Trees have life force

• The Earth is flat

• Apples generate a magnetic field

What did Newton hypothesize about the moon's motion?

• It was being pulled toward Earth but missing due to its sideways motion

• It was moving away from Earth

• It was being pulled by the sun only

• It was stationary

How did Newton describe the gravitational force in his equation?

• Proportional to the sum of the masses

• Directly proportional to the distance

• Inversely proportional to the distance

• Proportional to the product of the masses divided by the square of the distance

What constant did Newton introduce in his gravitational equation?

• The universal gravitational constant, G

• The Avogadro constant

• The Planck constant

• The speed of light constant

Which law describes the elliptical orbits of planets?

• Newton's law of universal gravitation

• Newton's first law of motion

• Kepler's first law

• Kepler's third law

According to Kepler's second law, what happens when a planet is closer to the sun?

• It moves slower and sweeps a smaller area

• It moves faster and sweeps a larger area

• It moves faster but sweeps the same area as when it is farther

• It stops moving

What did Newton prove using his laws of motion and calculus in relation to Kepler's laws?

• The orbits are perfectly stable

• The elliptical nature of orbits

• The orbits are random

• The orbits are circular

What is the gravitational acceleration at Mars's surface as used by NASA for testing?

• 9.8 meters per second squared

• 5.5 meters per second squared

• 3.7 meters per second squared

• 1.6 meters per second squared

How does NASA use Newton's law of universal gravitation today?

• To explore underwater environments

• To calculate trajectories for interstellar travel

• To develop quantum computers

• To simulate Martian gravity for astronaut training