If i bow a violin string exactly at 1/3rd of the length，what partials will be missing ？

why do we wrap the strings of a bass or cello？

The volume of some air, assumed to be an ideal gas, in the cylinder of a car engine is 540cm^3 at a pressure of 1.1 x 10^5 Pa and a Temperature of 27 Degree celsius. The air is suddenly compressed, so that no thermal energy enters or leaves the gas, to a volume of 30cm^3. The pressure rises to 6.5 x 10^6 Pa.

Determine the Temperature of the gas after compression.

Rutherford's experiments showed that positive charges in atoms is not uniformly throughout the atom. Describe his experimental set up, results and conclusions

Due to tides mean sea level off of Newport Beach reaches a height of 1.3 meters during high

tide and 0.3 meters during low tide. Successive high tides occur every 12 hours (43,200

seconds). A buoy with mass m = 40 kg is floating in the ocean off of Newport Beach.

1) Relevant concepts/equations. (5 points.)

2) Assume we begin to measure the buoy’s displacement at High tide which occurs exactly

at 12:00 am (0 seconds). Also assume we can model the buoy’s displacement as a simple

undamped oscillation. What is the Amplitude and phase angle for the buoy’s

displacement? (10 points)

3) During one half cycle of six hours (21600 seconds), the buoy’s displacement passes

through an angle of 180 degrees. From this information, what is the angular frequency

ω of the buoy? (5 points)

4) Using your previous answer, what is the force constant ‘k’ acting on the buoy? (5 points)

5) What is the maximum velocity of the buoy? What is the maximum acceleration of the

buoy? (10 points)

6) What is the energy of the buoy due to tidal displacement? (5 points)

7) How much work is done during one low tide to high tide cycle? How much Power per

hour is required to accomplish this? (Assume g = 9.81 m/s^2 compare your answer to a

65W light bulb which uses 65 watts per hour). (10 points)

what is wolf tone with respect to string instrument behavior？

the waveform of a flute is much simpler than that of an clarinet，why？

Captain Science, unmasker of fuzzy thinkers and proponent of cosmic truth, drops a 35 kg bowling ball on a stiff spring from a height of 1.0 m and finds that the spring compresses 2 cm.  If he drops the bowling ball from a height of 4.0 m, how much will the spring compress?

8 cm

1 cm

16 cm

2 cm

4 cm

The volume of a cylinder is V space equals space pi space r squared space h, where r is the radius of the circular faces and h is the height of the cylinder. Your measurements show that the mean value of r is 21 cm and its statistical and instrumental uncertainties turned out to be 0.10 cm and 0.20 cm, respectively. Likewise, that of h are 13 cm for the mean, 0.2 cm (statistical) and 0.3 cm (instrumental) for its uncertainties. What can you say about which source of uncertainty has the largest contribution to the overall uncertainty of V ? What would you need to do to improve (reduce) the uncertainty on your calculation of V?

A moving ball (ball #1) makes a perfectly elastic collision with a stationary ball (ball #2). After the collision it is observed that the speed of ball #2 is five times that of ball #1. Determine the angles θ1 and θ2 that the two balls scatter as measured from the initial direction of ball #1. You may assume that the two balls have identical masses, and you may need the identity

sin2(x) + cos2(x) = 1.

Please explain any concepts and how you got your answer.

2)

A bullet having a mass of m = 0.005 kg is fired toward a wooden block that is initially at rest on a wooden floor. The mass of the wooden block is M = 4.0 kg.

1. a.) Determine the minimum speed that the bullet must strike the block if it is to cause the block to start sliding along the floor. You may assume that it takes about T = 0.05 seconds for the bullet to come to rest while embedding into the block.

2. b.) Assuming the bullet hits the block at the speed computed in part (a), determine how far the wooden block (with the bullet embedded in it) will slide along the wooden floor before coming to rest.

A solid disk with a mass of 0.85 kg starts at the top of a 0.79 m tall hill and rolls down without slipping. What is the translational speed of the disk at the bottom of the hill? What fraction of the disk's kinetic energy is rotational at the bottom of the hill?

You are standing 2.50m directly in front of one of the two loudspeakers shown in the figure. They are 3.00m apart and both are playing a 686Hz tone in phase.

As you begin to walk directly away from the speaker, at what distances from the speaker do you hear a minimum sound intensity? The room temperature is 20?C.

Enter your answers numerically in increasing order separated by commas.

A block is placed on a plane inclined at 35 degrees relative to the horizontal. If the bloc k slides down the plane with an acceleration of magnitude g/3, determine the coefficient of the kinetic friction between the block and plane.

To a rough approximation, the Earth can be treated as a greybody sphere with uniform temperature, absorptance ? = 0.70 and emissivity ? = 0.61. The low absorptance is largely due to reflection of the incoming sunlight by clouds and ice, while the low emissivity is largely due to greenhouse gases in the atmosphere.

Q1) Over timescales of decades, the total solar irradiance at the Earth varies between about 1360.3 W/m² and 1362.0 W/m² . Using the greybody Earth approximation, how large of a temperature change can be expected due to these natural changes in solar irradiance? [Answer in K as a positive number.]

Q2) Over the last century, the amount of CO2 in the atmosphere has increased dramatically, which has resulted in a change in ? from 0.62 to 0.61. Using the greybody Earth approximation, how large of a temperature change can be expected due to this change in emissivity? [Answer in K as a positive number.]

Q3) The average temperature of the Earth is about 15 ^oC. Assuming a greybody surface, at what wavelength does the Earth emit most intensely? [Answer in µm].

A 283 g air track glider moving at 0.69 m/s on a 2.4 m long air track collides elastically with a 467 g glider at rest in the middle of the horizontal track. The end of the track over which the struck glider moves is not frictionless, and the glider moves with a coefficient of kinetic friciton = 0.02 with respect to the track. Will the glider reach the end of the track? Neglect the length of the gliders.