Question 1

Centripetal force applies to a body ___.&#10;A) in circular motion&#10;B) in linear motion&#10;C) in gravitation of the Earth only&#10;D) sitting still

Accepted Answer

Centripetal force is required for an object to move in a circular path. It acts towards the center of the circle around which the object is moving, keeping it in its circular path.

Question 2

To find the centripetal force equation, we must _____ the velocity.&#10;A) cube&#10;B) divide&#10;C) square&#10;D) not use

Accepted Answer

The centripetal force equation involves squaring the velocity.

Question 3

Using the centripetal acceleration equation and knowing the velocity and radius we can find the
_____.

A) mass of the body being orbited
B) mass of body that is orbiting the object
C) radius of other body
D) acceleration of other body

mass of the body being orbited

Accepted Answer

The centripetal acceleration equation allows for the calculation of the mass of the body being orbited when the gravitational force is considered as the centripetal force. This is because the gravitational force depends on the mass of both objects and the distance between them, and when rearranged to solve for one of the masses, it requires knowledge of the velocity and radius (distance) of the orbiting body.

Question 4

The sum of the masses of the Sun and Jupiter is equal to&#10;A) the square of Jupiter's average distance from the Sun in AU divided by the cube of Jupiter's period in years.&#10;B) the cube of Jupiter's average distance from the Sun in AU divided by the square of Jupiter's period in years.&#10;C) the square of Jupiter's period in years divided by the cube of Jupiter's average distance from the Sun in AU.&#10;D) the cube of Jupiter's period in years divided by the square of Jupiter's average distance from the Sun in AU.

Accepted Answer

This is a direct application of Kepler's third law of planetary motion, which states that the square of the orbital period of a planet (in years) is directly proportional to the cube of the semi-major axis of its orbit (in astronomical units, AU). When Kepler's third law is expressed in terms of masses, it shows that the sum of the masses of two bodies (like the Sun and Jupiter) is proportional to the cube of the distance between them divided by the square of their orbital period.

Question 5

To determine the mass of an object you need to know _____ and _____ from the other body you orbit.

Accepted Answer

The answer of To determine the mass of an object...

Question 6

We can find the mass of a star if we know the __________ and ___________ speed of a planet's orbit around the star.

Accepted Answer

The answer of We can find the mass of a...

Question 7

A centripetal force on an object moving in a circle always points toward the center of the circle.

Accepted Answer

Centripetal force is defined as the force that is directed toward the center of the circle along which an object is moving in a circular path, causing the object to maintain its circular motion.

Question 8

We can use Newton's version of Kepler's 3rd law to measure the masses of stars.

Accepted Answer

Newton's version of Kepler's third law allows us to calculate the masses of two objects in orbit around each other (such as a star and a planet, or a binary star system) by using the orbital period and the distance between the objects. This method is a fundamental tool in astrophysics for measuring the masses of stars.

Deck 17: Measuring a Bodys Mass Using Orbital Motion