1) Describe the basic principles of Fluorescence Correlation Spectroscopy (FCS). What do you measure in an FCS experiments and how do you perform the measurements.

In which situation is mechanical energy conserved?

A. a parachutist descends at constant speed

B. a car slows down without braking along a flat road

C. a heavy crate is raised at constant speed via a rope and pulley system

D. a sled accelerates as it slides down a frictionless inclined plane

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Two spaceships have the same mass. Spaceship A has kinetic energy K and spaceship B has kinetic energy 16K. What is the ratio of their speeds, vA/vB?

A. 1/16

B. 1/8

C. 2/1

D.  1/4

What will be the difference in SIL of the sounds from two loudspeakers, one with an efficiency of 2.1% and one with an efficiency of 10.3%. Assume that all other variables, including the electrical power supplied, are the same in the two cases.

Block 1 (0.5 kg) travels with an initial velocity of [ 40i ] + [ 60j ] m/s and then collides with block 2 (0.5 kg) traveling with an initial velocity of [ -40i ] + [ -40j ] m/s.
After the collision, block 1 has a final momentum of [ 5i ] + [ -25j ] kg*m/s. Assume that no external forces are present and therefore the momentum for the system of blocks is conserved.

What is the initial momentum of block 1?
i +   j kg*m/s

What is the initial momentum of block 2?
i +   j kg*m/s

What is the total initial momentum of the system of blocks?
i +   j kg*m/s

What is the change in momentum for block 1? (notice that you are given the final momentum for block 1.)
i +   j kg*m/s

What is the change in momentum for block 2?
i +   j kg*m/s

What is the final momentum of block 2?
i +   j kg*m/s

What is the total final momentum of the system of blocks?
i +   j kg*m/s

What is the total change of momentum of the system of blocks?
i +   j kg*m/s

What are the initial kinetic energies of block 1, block 2, and the system of blocks?
Block 1:  J
Block 2:  J
System of blocks:  J

What are the final kinetic energies of block 1, block 2, and the system of blocks?
Block 1:  J
Block 2:  J
System of blocks:  J

What is the change in kinetic energy of the system of blocks due to the collision?

Question 1: At a height of ten meters above the surface of a freshwater lake, a sound pulse is generated. The echo from the bottom of the lake returns to the point of origin 0.175 s later. The air and water temperatures are 20 ^oC. How deep is the lake?

Question2: A hunter is standing on flat ground between two vertical cliffs that are directly opposite one another. He is closer to one cliff than the other. He fires a gun and, after a while, hears three echoes. The second echo arrives 1.92 s after the first, and the third echo arrives 1.46 s after the second. Assuming that the speed of sound is 343 m/s and that there are no reflections of sound from the ground, find the distance (in m) between the cliffs.

You drop a 2.00 kg book to a friend who stands on the ground at distance D = 12.0 m below. Your friend's outstretched hands are at distance d = 1.80 m above the ground (see the figure). (a) What is the speed of the book when it reaches her hands? (b) If we substituted a second book with twice the mass, what would its speed be when it reaches her hands? (c) If, instead, the book were thrown down with initial speed 5.00 m/s, what would be the answer to (a)?

Two slits of width 2 μm, each in an opaque material, are separated by a center-to-center distance of 6 μm. A monochromatic light of wavelength 450 nm is incident on the double-slit. One finds a combined interference and diffraction pattern on the screen.

(a) How many peaks of the interference will be observed in the central maximum of the diffraction pattern?

(b) How many peaks of the interference will be observed if the slit width is doubled while keeping the distance between the slits same?

(c) How many peaks of interference will be observed if the slits are separated by twice the distance, that is, 12 μm,

while keeping the widths of the slits same?

(d) What will happen in (a) if instead of 450-nm light another light of wavelength 680 nm is used?

(e) What is the value of the ratio of the intensity of the central peak to the intensity of the next bright peak in (a)?

(f) Does this ratio depend on the wavelength of the light?

(g) Does this ratio depend on the width or separation of the slits?

We have to calculate the value of Power of an electric DC motor IN WATTS made from scratch. The only known values that we have are: The Voltage (V) which is 9V and the current (I) that we are using which is 3 A, also the value of "n" which is n= 90.16 m (the number of turns of the wire used in the motor)

I already asked here for this problem and someone answered this:

Voltage = 9 V, current = 3 A, number of turns = n = 90.16

Power of motor = n*V*I = 90.16*9*3=2434.32 Watt

But I don’t think this is correct since the motor has power in and power out. Can someone else help? Thank you!

Suppose that a parallel-plate capacitor has circular plates with radius R = 60.0 mm and a plate separation of 4.6 mm. Suppose also that a sinusoidal potential difference with a maximum value of 360 V and a frequency of 120 Hz is applied across the plates; that is

V=(360.0 V)sin((2.*π)*(120 Hz * t)).

Find Bmax(R), the maximum value of the induced magnetic field that occurs at r = R.

Find B(r = 30.0 mm).

Find B(r = 120.0 mm).

Find B(r = 180.0 mm).

A uniform thin rod of length 0.812 m is hung from a horizontal nail passing through a small hole in the rod located 0.043 m from the rod\'s end. When the rod is set swinging about the nail at small amplitude, what is the period of oscillation?

A long solenoid has 110 turns/cm and carries current i. An electron moves within the solenoid in a circle of radius 2.54 cm perpendicular to the solenoid axis. The speed of the electron is 0.0635c (c = speed of light, equal to 2.998 × 108 m/s). Find the current i in the solenoid.

A 5.5 F capacitor is charged to 35 V and is then connected across a 12-mH inductor. (a) How much energy is stored in the system? J (b) What is the frequency of oscillation of the circuit? Hz [3.33 points] (c) What is the maximum current in the circuit? A

A projectile is launched with initial velocity of 11 m/s at 30.5 degrees above the horizontal. - find the x-component of the initial velocity: - find the y-component of the initial velocity:

List and describe three real life situations in which is possible to experience centripetal force.