Why is ionization energy (W) roughly two to three times greater than ionization potential (I)?

Multiple choice: Suppose you are searching for exoplanets using the radial velocity and transit techniques. Which exoplanets are you most likely to find?

(a) Jovian exoplanets orbiting with a large semimajor axis.

(b) Jovian exoplanets orbiting with a small semimajor axis.

(c) Terrestrial exoplanets orbiting with a large semimajor axis.

(d) Terrestrial exoplanets orbiting with a small semimajor axis.

(e) There is an equal chance of finding both jovian and terrestrial exoplanets, and an equal chance of finding ones with large and small semimajor axes.

Multiple choice: Imagine a star with a single exoplanet orbiting it. If the exoplanet’s mass were doubled, the observed Doppler-shift variations of the star would be _______. If the semimajor axis of the exoplanet’s orbit were doubled, the observed Doppler-shift variations of the star would have _______.

(a) larger; a shorter period;

(b) smaller; a longer period;

(c) larger; a longer period;

(d) the same; the same period; or

(e) smaller; a shorter period.

Multiple choice: Suppose you are measuring the brightness change of a star over time due to an exoplanet orbiting the star. What are the properties of this exoplanet that you can deduce directly from the star’s light curve (plot of brightness vs. time)?

(a) The exoplanet’s orbital period, and the ratio of its radius to the host star’s radius.

(b) The exoplanet’s orbital period and its distance from the host star.

(c) The exoplanet’s distance from its host star, and the ratio of its mass to the host star’s mass.

(d) The exoplanet’s distance from its host star and the exoplanet’s density.

(e) The composition of the exoplanet’s atmosphere.

1. An oil drop with a mass of 2.48 x10^-15kg is balanced between two parallel, horizontal plates 1.7cm apart, maintained at a potential difference of 260 V. The upper plate is positive. Calculate the charge on the drop in coulombs and as a multiple of the elementary charge. Determine whether there is an excess or a deficit of electrons.

2. Two waves with equal speeds have frequencies of this wave is 40 Hz. What is the ratio of their wavelengths?

3. A wave on a string has a frequency of 0.83Hz and a wavelength of 0.56m. Determine the wavelength when a new wave of frequency 0.45Hz is established on this string and the wave speed does not change.

Astronomers have argued for long time, what it means that the universe is expanding. The observations of redshift and supernova brightness all agree:galaxies that are further away from the Milky Way are moving away faster than than galaxies that are nearby us. But does this affect our lives on Earth? How does our knowledge of an expanding universe help us understand our place in the universe as people?

Two Earth satellites, A and B, each of mass mmm = 930 kgkg , are launched into circular orbits around the Earth's center. Satellite A orbits at an altitude of 4000 kmkm , and satellite B orbits at an altitude of 12600 kmkm
What are the potential energies of the two satellites? (in Jules)
What are the kinetic energies of the two satellites?     (in Jules)
How much work would it require to change the orbit of satellite A to match that of satellite B? (in jules)
hint this is tricky problem

What would be a mathematical model for the diffusion constant, D?

If the average total displacement in either the x or y direction is 0 for all times, why is the displacement NOT zero? How does the displacement change with time?

The student observed the Moon to be about 12 degrees west of the Sun. What (major) phase will the Moon be in one day later? explain

1. A 31 kg crate full of fruits is placed on an incline that is 17◦ below the horizontal. The crate is connected to a spring that is anchored to a vertical wall, such that the spring is parallel to the surface of the incline.

(a) If the crate was connected to the spring at equilibrium length, and then allowed to stretch the spring until the crate comes to rest, determine the spring constant. Assume that the incline is frictionless and that the change in length of the spring is 2.13 m.

(b) If there is friction between the incline and the crate, would the spring stretch more, or less than if the incline is frictionless? You must use concepts pertaining to work and energy.

2. David is running with a horizontal velocity, along level ground. While running, he encounters a 2.51 m vine of negligible mass; the vine was hanging vertically from a tall tree limb and the end of the vine is directly level with his center of mass. David decides to grab the vine and swing, because he loves experiencing uniform circular motion. At the maximum height, David takes mental note that the angle the vine makes with the vertical is 21o . Ignore any elastic properties the vine may have.

(a) At the instant David grabs the vine, he is undergoing circular motion. Identify the external force on David that is supplying the centripetal force for his motion.

(b) Determine David’s centripetal acceleration.
(c) Determine the magnitude of the external force identified above, at the beginning of the swing.

Explain the relationship between milliamperage and exposure time with radiation production and image receptor exposure.

A pendulum consists of a ball of mass 3.0 kg on a string of length 4.0 m. The ball is pulled back untilits center has risen to a height of 0.80 m. The ball is released such that it strikes a 1.0 kg block at thebottom of its swing. The block comes to a rest after traveling 2.0 m across a surface withμk= 0.15.What is the speed of the ball right after the collision? Is the collision elastic?

7. Consider two noninteracting particles in a 1D simple harmonic oscillator (SHO) potential, which has 1-particle spatial wavefunctions ψ n ( x), where n = 0, 1, 2, … (we ignore spin by assuming both particles have the same spin quantum number or are spin 0). These wavefunctions are normalized to 1 and satisfy ψ n * ( x)ψ m ( x)dx −∞ ∞ ∫ = 0 when n ≠ m , i.e., they are orthogonal. The energies are !ω0 n + 1 2 ( ) . (a) (4 pts) Using the ψ n ( x), write the normalized wave function for two particles Ψ(1, 2) in the lowest energy state for the cases where they are distinguishable, bosons, or fermions. Be careful about symmetry. (b) (2 pts) What is the total energy (in terms of !ω0 ) and degeneracy for each case? (c) (2 pts) Using the shorthand (nm) − (mn) notation for antisymmetric wavefunctions, write all possible combinations of two fermions to be in the 2nd excited state. (d) (2 pts) What is the total energy for (c)?

Two students use a uniform slab of wood (mass= 10 Kg, length = 2.0m) in order to move a delicate but heavy piece of lab equipment (mass = 55 kg). The piece of equipment is placed 0.35 m from one of the students (note: one of the students is stronger than the other, but they succeed in keeping the slab perfectly level).

Find the force that the student nearest to the load applies to the slab:

Silicon solar cells vs. thin-film solar cells Compare silicon solar cells with thin-film solar cells in the following aspects: (1) device structure; (2) working principle; (3) efficiency; and (4) cost. Need informative answer for my clear understandings.

An 80-kg person stands at one end of a 130-kg boat. He then walks to the other end of the boat so that the boat moves 80 cm with respect to the bottom of the lake.

A. What is the length of the boat?

B. How much did the center of mass of the person-boat system move when the person walked from one end to the other?

1. Describe the main differences between the inner and outer planets.

2. Describe the surface of Venus?

3. What evidence is there of past large bodies of water on Mars?

4. Describe some of the geology of Mars?