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Mechanics and Gravitation: 17 Multiple choice questions

(See attached file for full problem description) --- Mark the following statements true or false. 1. (b) A conservative force can do no work on an object. 2. (a) Potential energy is necessarily a positive quantity. (b) Kinetic energy is necessarily a positive quantity. (c) The change in potential energy of an o

Force Problems5/6/7

Every few hundred years most of the plants line up on the same side of the Sun. Calculate the total forces on the Earth due to Venus, Jupiter, and Saturn, assuming all four plants are in line. The masses are Mv = 0.815Me, M3=318Me, Ms=95.1Me and their mean distance from the sun are 108,150, 778 and 1430 million km respectively.

Physics Questions

1. (a) Calculate the mass of the earth given the acceleration of gravity at the north pole is 9.830 m/s^2 and the radius of the earth is 6371 km from pole to pole. (b) Compare this with the accepted value of 5.979 x 10^24 kg. 2. (a) Calculate the ratio r^3/T^2 for the moon's orbit about the earth, where r is the average radi

2 Physics Problems

1. Suppose we roll a ball off a table, at a speed of 2.0 m/s. This means that the initial velocity is completely horizontal; there is no initial component of velocity in the vertical direction. The table is 1.3 meters high. (A) How much time does it take the ball to hit the ground after leaving the table? (B) How far does the ba

Planetary evolution and the early solar system

F. Which is hotter, Mercury or Venus? Why? h. Explain why there are two general families of planets, rocky terrestrial and gaseous jovian. j. What knowledge do comets and asteroids provide to studies of the origin of the solar system?

Discussion questions - eclipses, lunar phase changes, Newton

1. Explain what causes a lunar eclipse. Explain what causes a solar eclipse. Include a diagram. Why don't eclipses occur every month? 2. Describe the phase changes of the Earth that one would see if viewed from the Moon. 3. It is said that Newton unified Earth and the Universe. Explain.

2 problems on Kinematics: Cheetah hunting and astronaut on distant planet...

3) A cheetah is hunting. Its prey run for 2.5 s at a constant velocity of +6.9 m/s. Starting from rest, what constant acceleration must the + cheetah maintain in order to run the same distance as its prey runs in the same time? 4) An astronaut on a distant planet wants to determine its acceleration due to gravity. The astro

Three classical mechanics problems

(See attached file for full problem description) --- 1. A rock is thrown straight up from the earth's surface. Which one of the following statements concerning the net force acting on the rock at the top of its path is true? A It is equal to the weight of the rock. B It is instantaneously equal to zero newtons.

Forces and Newton's Laws of Motion

1. An airplane has a mass of 3.1 X 104 kg and takes off under the influence of a constant net force of 3.7 X 104 N. What is the net force that acts on the plane's 78-kg pilot? 3. In the amusement park ride known as Magic Mountain Superman, powerful magnets accelerate a car and its riders from rest to 45 m/s (about 100 mi/h)

Earth axis

How would the seasons be affected if the Earth's axis were not inclined 23 1/2 degrees from the plane of the ecliptic, but were instead perpendicular to that orbital plane?

Radius, Mass of Planets and Period of a Pendulum

My problem is understanding this because I have to calculate the mass and radius of 3 planets along with the graviational acceleration and then find the period of a 2 meter long pendulum on each planet for the assignment. The instructor posted a formula that he used in Excel but there was no explanation. The formula: =6

Masses of X-Ray Binary Stars

Is it possible to calculate the masses of the stars in an x-ray binary system when all i know of the system is that; one of the stars is a main sequences star of spectral type K5 measured from optical spectroscopy. The companion star is believed to be a neutron star with no distinct pulsations, however the x-ray emission has exh

Rotational Motion of New York City

New York City is traveling around at a tangential speed of about 353 m/s (i.e., 790 mi/h) as the Earth spins. Assuming the planet is a sphere of radius 6371 km, how long is the perpendicular from the city to the spin axis? Compute the city's latitude (i.e., the angle measured above or below the equator).

Theory of Relativity

1. Two airplanes are flying side by side at the same altitude. Plane A is slowly overtaking plane B at 4 km/h. A stewardess in plane A is walking toward the rear of the plane at a speed of 2 km/h, and a passenger is walking toward the front at 2 km/h. What are their speeds relative to a passenger watching them from place B? 2

Properties of Circular Orbits

The motivation for Isaac Newton to discover his laws of motion was to explain the properties of planetary orbits that were observed by Tycho Brahe and analyzed by Johannes Kepler. A good starting point for understanding this (as well as the speed of the space shuttle and the height of geostationary satellites) is the simplest or

Potential Energy Calculations

**Please see attachment for complete questions Required: a) Consider a uniform gravitational field (a fair approximation near the surface of a planet). Find ... {see attachment} b) Consider the force exerted by a spring that obeys Hooke's law. Find {see attachment} c) Finally, consider the gravitational force generat

Gravitation problem

A hypothetical planet has a radius 2.5 times that of Earth, but has the same mass. What is the acceleration due to gravity near its surface?

Gravity: Magnitude of force, shortest period of rotation

See the attached file for the diagrams. 1. In the picture two spheres of mass m and a third sphere of mass M form an equilateral triangle and a fourth sphere of mass m 4 is at the center of the triangle. The net gravitational force on that central sphere from the three other spheres is zero. (a) What is M in terms of m ? (b)


What does it mean when scientist said reality is rational?

Spacecraft orbiting -- need to find the period

A spacecraft is in orbit around Jupiter. The radius of the orbit is 3.0 times the radius of Jupiter (RJupiter = 71,500 km). The gravitational acceleration at the surface of Jupiter (the surface is defined as the above radius) is 23 m/s2. Without using any other information about Jupiter, what is the period of the spacecraft's

Mass, force, gravity: What is more important, the planet Uranus or the physician?

The mass of Uranus is 9x10 to the 25th kg. Its mean distance from the earth is about 3x10 to the 12th meters. Estimate your mass in kilograms at birth. Then find the force exerted upon your body at birth by Uranus. Is it very large? Next assume that you were delivered by a 100 kg physician who was on the average about 10 cm from

Using a Spectrograph for Saturns Rings

A.) How can a spectrogrph be used to indicate that the rings of Saturn are not solid? B.) Astronomers in the 1940's had difficulty measuring the amount of water in the Martian atmosphere spectroscopically, becuase the Earth's atmospheric water got in the way. They could not yet fly above our atmosphere. How could the spectral l