Universal Gravitation

Question 1

If the radius of Earth decreased (with no change in mass) your weight would…?

Answer 1

Increase because gravity grows stronger as distance decreases

Question 2

Why did Newton think there was a force acting on the moon?

Answer 2

Because the moon always moved in a curved path (not linear)

Question 3

Compared to the current gravitational field on the surface of Earth, the gravitational field well below Earth’s surface is…?

Answer 3

Smaller

Question 4

What is most significant about the weakness of gravity?

Answer 4

Easily identified gravitational forces must involve one or more large masses

Question 5

During circular motion, the net force on the object is directed towards…?

Answer 5

The center of the curve

Question 6

Tangential Velocity

Answer 6

The “sideways” velocity of an object that is perpendicular to the pull of gravity

Question 7

What type of relationship do force, mass, and distance share?

Answer 7

A square inverse relationship

Question 8

What is the value of G on Earth?

Answer 8

6.67 x 10^-11 N x m^2/kg^2

Question 9

Period

Answer 9

The time interval in which an object takes to go around its circular path one time

Question 10

Frequency

Answer 10

The number of revolutions (periods) per second. Measured in Hz or s^-1

Question 11

Centrifugal Force/Acceleration

Answer 11

An apparent force that acts outward on a body moving around a center, often due to inertia

Question 12

Apparent Weight

Answer 12

The sum of net forces that make you feel either heavier/lighter in different circumstances

Question 13

At the bottom of a dip in circular motion, your apparent weight will be…?

Answer 13

Greater

Question 14

At the top of a crest in circular motion, your apparent weight will be…?

Answer 14

Less

Question 15

Critical Speed

Answer 15

The slowest speed at which a vehicle can complete a circular path/curve

Question 16

Orbit

Answer 16

When a projectile is launched with enough force that it never travels all the way back to the ground and stays in a constant free-fall, traveling around Earth

Question 17

What is the value of g dependent on?

Answer 17

The radius and mass of said planet

Question 18

Mass

Answer 18

The measure of inertia that each object possesses no matter where it is located, hence making mass a property of objects

Question 19

Weight

Answer 19

The force exerted on an object due to gravity (most often downwards as expressed as Fmg in free-body diagrams)

Question 20

The attraction between different objects/masses is…?

Answer 20

Proportional, every object exerts an equal force on one another that is equivalent to the mass of each object

Question 21

Is the speed of circular motion constant?

Answer 21

Yes

Question 22

Is the velocity of circular motion constant?

Answer 22

No, because the direction of travel is constantly changing

Question 23

What is the weight of an astronaut in an orbiting space shuttle?

Answer 23

The astronaut’s apparent weight would be zero because they are in free-fall