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Acoustics Fluid Wave Motion

A fluid is rotating with a velocity of , and , where β is a constant and c is the speed of sound and is the density. When can a ray of sound move in a closed circle? See attached file for full problem description.

Electron in orbit of a hydrogen like atom.

An external electron in a hydrogen like atom is moving around the nucleus in a circular orbit of radius R. A weak magnetic field perpendicular to the orbit is slowly turned on and increases to a magnitude B. assuming that the radius of the orbit does not change, find: a. the magnitude and direction(with respect to B) of magne

Earth and Sun System Calculations

In this problem you are to make use of the formula P^2 = 4(pi)^2/mu *a^3, together with the fact that mu = G(m1 + m2). Assume, as is approximately correct, that the semi-major axis for the Earth's orbit about the Sun is 93 million miles and that the period is 365 days. Also assume that the semi-major axis for the Moon's orbit ab

De Broglie Hypothesis of Wavelength

I need some help with these questions on de Broglie hypothesis: (See attachment for better formula symbols) 1.a. Show how the de Broglie hypothesis for the wavelength of an electron can lead to an explanation of the condition for quantization of orbital angular momentum in the Bohr model for hydrogen atom. b. Show that the f

Calculating gravitation for Halley's Comet

The orbital period of Halley's Comet is calculated to be 75.5 years. Many other comets have orbits that extend much farther from the sun, and hence have much longer periods. At aphelion, a typical long-period comet is about from the sun; at perihelion, it passes inside the earth's orbit. 1. Estimate the orbital period of suc

Gravitation of a Satellite

If a satellite is in a sufficiently low orbit, it will encounter air drag from the earth's atmosphere. Since air drag does negative work (the force of air drag is directed opposite the motion), the mechanical energy will decrease. According to the following equation: (See attached file for full problem description) E= - GmEm/

Newton's Law of Gravitation and Masses

Please see attachment for full problem description. --- Learning Goal: To understand Newton's law of gravitation and the distinction between inertial and gravitational masses. In this problem, you will practice using Newton's law of gravitation. According to that law, the magnitude of the gravitational force between two s

Set of four problems on circular and planetary motion.

1.An object is attached to a 1.60 meter rope and twirled in a horizontal circle on a frictionless table. The tension on the string is 585 Newtons and the ball takes 1.46 seconds to complete one revolution. Determine the mass of the object (in kg to two decimal places). 1a. if the mass of the object were doubled (keeping a c

Gravitation: Force, Field and Satellite

(See attached file for full problem description with equations and diagram) 1. A 2150 kg satellite used in a cellular telephone network is in a circular orbit at a height of 780 km above the surface of the earth. What is the gravitational force on the satellite? What fraction is this of its weight at the surface of the earth?

Magnetic computer Disk

(See attached file for full problem description) --- A magnetic computer disk 8.0 cm in diameter is initially at rest. A small dot is painted on the edge of the disk. The disk accelerates at for , then coasts at a steady angular velocity for another . Part A What is the speed of the dot at t = 1.0 s? Part B Through ho

Solving Physics Questions

1. Give an example of a situation in which there is a force and a non-zero displacement, but the force does no work. Explain why it does no work. 2. What is a conservative force? 3. (a) Calculate the work done on a 1500 kg elevator by its cable to lift it 40.0 m at constant speed, assuming friction averages 100 N. (b) What i

Kepler's Laws and Earth Satellites

Calculate the center of mass of the Earth-Moon system, if the radius of the earth is 6380 km is it inside the earth? For the MOON and the EARTH [M sub E = 6.0 x 10^24kg, M sub M = 7.4 x 10^22 kg], [R sub orbit = 3.84 x 10^8 m]

Answers needed for different questions of general chemistry

Question 16 Multiple Choice 20 points In which pair are the elements most similar in their chemical properties? Ca and Ba S and P Ag and Rb Cs and Xe Question 17 True/False 20 points In Lewis dot structures, lone pairs are valence electrons not involved in covalent bonding. Tr

Kepler's Laws and Venus Satellites

Venus has a rotational period of 243 days. What would be the altitude of a synchronous satellite for this planet (similar to geosynchronous satellite on the Earth)?

Orbit Frequency of an Electron

The hydrogen atom may be described as a postively charged proton surrounded by an orbiting, negatively charged electron. In a simple model, the electron is in a circular orbit of radius r= 5.29 x 10( to the negative 11) m about a stationary proton. The mass of the proton is mp= 1.67 x 10 (negative 27)kg and the mass of the proto


Prove that if G is a finite group of prime power order p^a, then the center Z(G) can not be the identity subgroup.

Quiz Question

9. Which answer shows a pattern from the closest object to the Earth to the farthest from the Earth? (a) Space Shuttle in orbit --- Stars --- Pluto (b) Pluto --- Space Shuttle in orbit --- Stars (c) Stars --- Space Shuttle in orbit --- Pluto (d) Stars --- Pluto --- Space Shuttle in orbit (e) Space Shuttle in orbit --- Plu

Quantum states of ions

Please see the attached file. According to the Schrodinger atomic model, each quantum state of an atom or ion can be labelled using two quantum numbers n and l. Write down a formula for the energy of each of the quantum states of the hydrogen like boron ion B4+. For a given value of n, state how the number of quantum s

Photon emission during transition

The electron of a hydrogen atom is initially at the orbit n=4. If this electron first goes to the orbit n=3 and then to the orbit n=2 and then to the orbit n=1, how many photons are emitted during these transitions? How many photons are emitted if the electron directly falls from the orbit n=4 to the orbit n=1?

Space station orientation for maximum voltage difference

Imagine a space station module shaped like a cylinder 30m long and 5m in diameter orbiting close to the earth above the earth's equater. What would be the maximum potential difference that could develop between the ends of the module. (I know that potential difference=EL but how do I find E? It is also equal to VB/C or v*magnet

Particles in orbit

The solar wind is a continuous stream of particles, mostly protons and electrons, moving away from the Sun. When the particles encounter Earth's upper atmosphere, they are moving at speeds of several hundred km/s. If such a particle reaches Earth's upper atmosphere with a speed of 92 km/s, how fast was it moving when it cross

Use Newton's laws to find the orbital velocity of the atomic electron.

A hydrogen atom when in its lowest energy state consists of a proton of charge +e and an electron of charge -e and mass 9.1x10-31 kg. In the Bohr model of the atom, the electron moves around the nucleus in a circular orbit of radius 0.51x10-10 m. Determine the speed that another electron, starting very far away from the hydrogen