Explain the motion of a rattleback. Do not just describe motion Explain the motion.

Consider a 4-mg raindrop that falls from a cloud at a height of 2 km.

Part a) If we neglect air resistance, what would be the speed of the raindrop when it reaches the ground? Assume that the falling raindrop maintains its shape so that no energy is lost to the deformation of the droplet.

________ m/s

Part b) When the raindrop reaches the ground, it won't kill you or even bruise you because its terminal velocity is just 10 m/s. Calculate the work done by the air resistance on the raindrop. Recall that positive work done on an object/system increases the energy of that object/system. Again, assume that the falling raindrop maintains its shape so that no energy is lost to the deformation of the droplet.

________ Joules

Part c) What percentage of the raindrop's initial mechanical energy was lost to air resistance? (Based on your answers, ask yourself if you think it is reasonable to ignore air resistance when evaluating the fall of a raindrop from the sky.)

________ %

why is GaN has wide band gap compare with Si?

Why does Gravity Exist? Why is any body able to attract another? Where does that energy emerge from? Is there anything like gravitational repulsion?

Derive an expression of the mean free path of a gas molecule assuming a hard sphere collision. Calculate the ratio of the mean free path of CO molecules in a vessel at a pressure P1=10-4 Torr at 300 K to that at a pressure P2=10-9 Torr at the same temperature. (CO molecules d =0.73nm)

What type of measuring device relies on Zeroth’s Law and how does it do this?

The temperature outside is 0 degrees Fahrenheit. What is the temperature in Kelvin?

An isolated system absorbs a heat transfer of 45J and performs 20 J of work. What is the internal energy of the system?

An isolated system contains some amount of internal energy. If 5 J of heat are transferred into the system, but the internal energy remains the same, how much work must be done by the system?

How much work is done by a jet engine that exerts 245 N of force over a distance of 1 km?

A gas maintains a constant pressure of 45 N/m² while being heated. The resulting change in volume is 0.78 m³. What is the work done by the gas?

The same gas in problem 6 had an internal energy of 85 J and a final volume of 2 m³. What is the enthalpy (H) of the gas?

The combustion process inside a jet engine creates 450 J of heat and does 110 J of work spinning a turbine shaft. What is the change in specific enthalpy of the gas?

Through an irreversible process, object A transfers 96 J of heat to object B. The resulting temperature of the system is 456 K. What is the entropy of the system?

For an ideal gas, if the pressure remains the same but the volume is doubled, what would you expect to happen to the temperature? Why?   **Hint: use the equation of state to help justify your answer.

The size of an object parallel to the axis of rotation does not enter into the calculation of its moment of inertia. Why?

Why are the higher-order spectra more accurate than the first-order spectrum in determining wavelengths of light?

a Discuss the difference between the continuous spectrum obtained with a grating and one obtained with a prism. (b). Which color is deviated most in each case? Why?

Two pendulums have the same dimensions (length {L}) and total mass (m). Pendulum \texttip{A}{A} is a very small ball swinging at the end of a uniform massless bar. In pendulum \texttip{B}{B}, half the mass is in the ball and half is in the uniform bar.

A)Find the period of pendulum A for small oscillations.

B)Find the period of pendulum B for small oscillations.

C)Please be sure to include the specific calculations of the moment of inertia and the distance to the center of mass for pendulum B.

D) By what fraction is the period of one pendulum smaller than the other?

1. The fact that a trumpet and a saxaphone sound different when playing the same fundamental frequency is best explained by which concept listed below?

a. The Doppler Effect
b. Sound wave reflection
c. Beats
d. Timbre

2. A single-frequency air horn (f = 800 Hz) is sounded by a rider in a roller coaster moving toward you at 47 m/s as you stand next to the track. What frequency do you hear? Assume the speed of sound to be 340 m/s.

a. 928 Hz
b. 1004 Hz
c. 1109 Hz
d. 832 Hz

3. Using the same scenario as question #2, now assume that you are a rider on a second coaster moving toward the sender. You both have the same speed relative to the ground. You hear a frequency of 1207 Hz. What is the frequency of the sender's air-horn?

a. 752 Hz
b. 834 Hz
c. 888 Hz
d. 914 Hz

Picture water flow of four straws, short and fat, short and thin, long and fat, and long and thin.

Think about how water would flow through two configurations of these same four straws:

One version where the four straws are taped end-to-end to make one long straw

The other version where all four straws are taped together side by side, so you would suck water through all four at the same time

Which of these two configurations produces the lowest current? Which produces the highest? Why?

Two loudspeakers are located 2.53 m apart on an outdoor stage. A listener is 21.4 m from one and 22.2 m from the other. During the sound check, a signal generator drives the two speakers in phase with the same amplitude and frequency. The transmitted frequency is swept through the audible range (20 Hz to 20 kHz). (a) What is the lowest frequency f_min,1 that gives minimum signal (destructive interference) at the listener's location? By what number must f_min,1 be multiplied to get (b) the second lowest frequency f_min,2 that gives minimum signal and (c) the third lowest frequency f_min,3 that gives minimum signal? (d) What is the lowest frequency f_max,1that gives maximum signal (constructive interference) at the listener’s location? By what number must f_max,1 be multiplied to get (e) the second lowest frequency f_max,2 that gives maximum signal and (f) the third lowest frequency f_max,3 that gives maximum signal? (Take the speed of sound to be 343 m/s.)

Answers to 3 significant digits. No scientific notation. Provide units. Thank you!

What is crystal field effect? Please state that in terms of Px, Py, and Pz orbits. (Please briefly description)

A block with mass m =7.5 kg is hung from a vertical spring. When the mass hangs in equilibrium, the spring stretches x = 0.25 m. While at this equilibrium position, the mass is then given an initial push downward at v = 4.1 m/s. The block oscillates on the spring without friction.

After t = 0.3 s what is the speed of the block?

What is the magnitude of the maximum acceleration of the block?

At t = 0.3 s what is the magnitude of the net force on the block?

Where is the potential energy of the system the greatest?

At the highest point of the oscillation.

At the new equilibrium position of the oscillation.

At the lowest point of the oscillation.