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Solar System

Incompressible flow around a cylinder

Verify that the potential Phi = U (r +a^2/r)*cos(theta)-2U*a*theta can represent such a flow about a solid cylinder of radius a. Find the tangential velocity at the surface of the cylinder. Use Bernoulli's equation to show that the pressure field is given by: p(a,theta) = C - 2*rho*U^2*(sin^2 theta + 2sin theta) Fin

Coriollis Force and Noninertial Frames

A particle is projected vertically upward from the surface of the earth at colatitude (polar angle) theta. It rises to a height (h << R_earth) and then falls back to the surface. Show that it strikes the ground at a distance (8/3)*omega*sin(theta)*Sqrt(2h^3/g) to the west of the initial position, where omega = angular velocit

Magnetic field due to a current carrying wire

Jumper cables used to start a stalled vehicle often carry a 15 A current. How strong is the magnetic field 16 cm away? What percentage of the Earth's magnetic field (5.00 E-5 T) is this?

This job accounts for weightless feelings.

A bungee jumper feels weightless as she falls toward the Earth. Obviously the force of gravity has not disappeared simply because she has jumped off a high platform. What accounts for the weightless feeling people get when they fall freely?

Density of Rock

A geologist finds that a moon rock whose mass is 8.80 kg has an apparent mass of 6.7 kg when submerged in water. What is the density of the rock? kg/m3

Four problems on mechanics

Please help with the following problems. 1. A car starts from rest and reaches a speed of 31m/s in 2 seconds. Calculate its acceleration, if this value stays the same then what it the speed 7 seconds later? 2. A ball is thrown off a very tall building with a velocity of 16 m/s. What is the speed of the ball after 1.1 seco

Haley's comet orbits the sun every 76 years, and was first observed in 240bce.

Haley's comet orbits the sun every 76 years, and was first observed in 240bce. Its orbit is highly elliptical, so that its closest approach to the sun (perihelion) is only 0.587 AU, while at its greatest distance (aphelion), the comet is 34.39 AU from the sun. (An AU, or astronomical unit, is the distance from earth to the sun,

Gravitation on Mars and Earth - weight and mass

1. Calculate (a) the gravitational acceleration on the surface of Mars and (b) the weight of a 0.50 kg rock on its surface. 2. A 10 kg monkey is 10^6 m above the earth's surface. (a) What is its weight there? (b) What is its mass there?

Density, Volume, Mass, Weight,

A gymnasium measures 40.0m x 20.0m x 12.0m. If the density of the air in the gym is 1.20 kg/meters cubed, than what is the weight of air in the room in pounds. Show all work.

Astronomy is the most ancient science.

Astronomy is the most ancient science. Discuss how the development of astronomy is interrelated with the development of civilization. Some possible relationships include astrology, the names of constellations, calendars, and the basic ideas of mankind's place in the universe.

Spacecraft Run Out of Fuel

Very far from earth (at R= infinity), a spacecraft has run out of fuel and its kinetic energy is zero. If only the gravitational force of the earth were to act on it (i.e., neglect the forces from the sun and other solar system objects), the spacecraft would eventually crash into the earth. The mass of the earth is M_e and its r

maximum length of a steel cable lowered into a mine

Although human beings have been able to fly hundreds of thousands of miles into outer space, getting inside the earth has proven much more difficult. The deepest mines ever drilled are only about 10 miles deep. To illustrate the difficulties associated with such drilling, consider the following: The density of steel is about

right ascension and declination of the point in the sky

Question 1 What are the right ascension and declination of the point in the sky where the ecliptic and the celestial equator intersect in March each year? The Sun crosses this point from the Southern Hemisphere to Northern Hemisphere in the sky. R.A. = _____ H _____ M Declination = __________ degrees __________ minut

Energy of a Hammer Dropped on Earth

For a hammer dropped on earth, the initial gravitational potential energy is 60.0 J. What would be the initial gravitational potential energy for the hammer on the moon (where the acceleration due to gravity is 1.67 m/s(squared) if it is released from the same height in both places? U(moon)= ?J What would be the initi

Displacement Vector

See the attached file. Could you please provide the answers and workings out to the following physics problems. 8. which one of the following quantities is a vector quantity? a) the age of the earth b) the mass of a football c) the earth's pull on your body d) the temperature of an iron bar e) the number of people atte

Force of Mutual Attraction

Consider 2 iron spheres, each with a Diameter of 100mm which are just touching. a) Compute the force of mutual attraction when the spheres are just touching b) At what distance ,r, from the center of the earth will the force of mutual attraction between the contacting spheres be equal to the force exerted by the earth on

Potential Energy and Gravitational Pull

Consider a 5-kg object interacting gravitationally with the earth. Imagine that we set up a standard reference frame with the z axis pointing vertically upward. If the interaction's potential energy when the object is at z = 5 m is -50 J, what is the approximate z-position of the object when it is at its reference separation fro

Potential Energies

Explain in everyday English and using formulas, the difference between 'electric potential' and 'electric potential energy'. Also explain, in the practical sense, why it matters that there is a difference. In other words, when will I ever see it? Also, explain why sometimes 'electrical' is interchanged with 'electrostatic' fo

The Net Gravitational Force on the Moon

The drawing (not to scale) shows one alignment of the sun, earth, and moon. The gravitational force FSM that the sun exerts on the moon is perpendicular to the force FEM that the earth exerts on the moon. The masses are: mass of the sun = 1.99 1030 kg, the mass of earth = 5.98 * 10^24 kg, mass of moon = 7.35 * 10^22 kg. The dis


12. The Universe according to the prevailing current body of evidence is likely to a. contract someday and implode on itself b. be an oscillator and right now it is simply in an expansion phase c. continue to expand forever d. heat up as the distance between galaxies increases 13.Select

Lorentz Force on an air plane due to earth magnetic field

Due to friction with the air, an airplane has acquired a net charge of 1.70 x 10^-5 C. The plane moves with a speed of 2.80 x 10^2 m/s at an angle with respect to the earth's magnetic field, the magnitude of which is 5.00 x 10^-5 T. The magnetic force on the airplane has a magnitude of 2.30 x 10^-7 N. What is the angle?

Modern Physics: Number of Cycles from Two Clocks

See attached file for full problem description. In the twin paradox, twin A remains on Earth while twin B travels a distance L, measured in the Earth's inertial frame, at a velocity v to a very distant solar system. In turning around for the return trip, the rocket malfunctions somewhat and achieves only a velocity ½ v. Fi

Pendulum Oscillations in the Earth

A pendulum clock works perfectly on the Earth. It is then taken to the Moon, which has 1/6 the gravity of Earth. a) Does it run fast or slow? b) If the clock is started at 12:00 a.m., what will it read after one Earth day (24hrs)?

Shuttle launched on moon and in vacuum.

Suppose a shuttle were launched from a launchpad on the Moon instead of the Earth's surface. What changes would we observe? Suppose it were launched from a launchpad in space in vacuum. Would it work? What changes would we observe? Explain your answer.

Classical Mechanics Homework Problems

See attached file for full problem description. 1. Two masses are released at the same height, and fall a very long distance under gravity, till they hit the ground. The masses are subject to air friction, which you should assume has the form —b17 for both masses, even if this mathematical form is not very accurate. Mass A

How much farther a person can jump on the Moon?

Determine how much farther a person can jump on the Moon as compared to the Earth if the take-off speed and angle are the same. The acceleration due to gravity on the Moon is one-sixth what it is on Earth.