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?

A brass ring of diameter 10.00 cm at 16.4°C is heated and slipped over an aluminum rod of diameter 10.01 cm at 16.4°C. Assume the average coefficients of linear expansion are constant.

(a) To what temperature must the combination be cooled to separate the two metals?

? °C

(b) What if the aluminum rod were 11.76 cm in diameter?

? °C

what causes fictitious force in a non-rotating reference frame?

7. What is the primary mechanism for maintaining homeostasis?

Select one:

a. positive feedback

b. negative feedback

c. intrinsic control

d. extrinsic control

e. homeostatic control

Feedback

The correct answer is: negative feedback plz explain a.b c d e all explain in short answer

Why does tension not appear in the universal wave equation?

How the world has reacted to global climate change aka greenhouse gasses rising. describe with evidence?

N12R.3Imagine you are the orbital engineer for the first NASA space shot to Ceres, the largest known asteroid. Ceres’s nearly circular orbit around the sun has a radius of R = 2.77 AU. After being launched from the earth, the probe will initially be in a circular orbit around the sun with the same radius (rc = 1.0 AU) and the same orbital speed Inline_Formula as the earth’s orbit. The probe’s rocket engines will then fire briefly to increase the probe’s speed to that speed Inline_Formula needed to put the probe into an elliptical orbit whose initial (and minimum) distance from the sun is rc = 1.0 AU and whose final (and largest) distance from the sun is R = 2.77 AU (this is a Hohmann transfer orbit). (a) How long will it take the probe to get from the earth to Ceres in such an orbit? (b) What is the speed Inline_Formulathat the probe has to have just after firing its engines to be inserted into this orbit? (Assume the duration of the boost is short enough that its distance from the sun is still nearly rc just after the engines have been fired.)