Question

1. isaac newton was the first person to formulate and test the law of

a. universal gravitation.
b. acceleration.
c. orbital velocity.
d. universal mass.

1. the spinning of earth on its axis is called

a. revolution.
b. precession.
c. rotation.
d. perihelion.

1. what is earth’s motion in its path around the sun called?

a. aphelion
b. rotation
c. precession
d. revolution

1. what is precession?

a. the tilt of earth’s axis in relation to the ecliptic
b. the rotation of earth as it moves around the sun
c. the faster orbital velocity of the planet at perihelion
d. the slow change in the direction in which earth’s axis tilts

Explanation:

• For question 7, Isaac Newton formulated the law of universal gravitation.
• For question 8, the spinning of Earth on its axis is rotation.
• For question 9, Earth's motion around the sun is revolution.
• For question 10, precession is the slow - change in the direction of Earth's axis tilt.

Answer:

1. a. universal gravitation
2. c. rotation
3. d. revolution
4. d. the slow change in the direction in which Earth’s axis tilts