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Millikan experiment, Compton effect, photoelectric effect

1. In a Millikan oil drop experiment the terminal velocity of the droplet is observed to be vt = 1.5 mm/s. The density of the oil is = 830 kg/m3 and the viscosity of air is = 1.82 10-5 kg/m s. Use the following equations to find the values below. Calculate the droplet radius. µm (b) Calculate the mass of the drop

motion of a cookie jar on an incline

Show ALL your work, including the equations used to solve the problems. A cookie jar is moving up a 40º incline. At a point 55 cm from the bottom of the incline (measured along the incline), it has a speed of 1.4 m/s. The coefficient of kinetic friction between jar and incline is 0.15. a) How much farther up the incline

Find Final Energy for Absorption of Photon by Electron

An electron in a 10.2 nm one dimensional box is excited from the ground state into a higher energy state by absorbing a photon of electromagnetic radiation with a wavelength of 1.369 10^-5 m. Determine the final energy state for this transition.

Classical mechanics: Motion in two dimension.

1. A river flows due east at 1.00 m/s. A boat crosses the river from the south shore to the north shore by maintaining a constant velocity of 9.0 m/s due north relative to the water. (a) What is the velocity of the boat relative to shore? (b) If the river is 280 m wide, how far downstream has the boat moved by the time it rea

Elastic Collision of Air-Track Glider

An air-track glider with an initial speed of 4.0 m/s has a head-on collision with another glider at rest that is three times as massive. What are the final speed and directions of the gliders if the collision is elastic? I believe the answer is V1 = -2.0 m/s and V2 = +2.0 m/s. I need to see each step and formula to solve this qu

What is the ratio of the masses of the two marbles?

A child playing marbles shoots a marble directly at another marble at rest. The first marble stops, and the second marble continues in a straight line with the same speed that the first marble had initially. What is the ratio of the masses of the two marbles? I need to see each step and formula to solve this question.

A block slides on a semicircular frictionless track.

A block slides on a semicircular frictionless track. If it starts from rest at position (A), what is its speed at the point marked (B)? A picture of the block and slide is attached as a jpeg file. I believe the answer is 3.7 m/s. I need to see each step and formula to solve this question.

Rotational and Linear Speed & Kinetic Energy

A full keg of beer weighs 170 lbf. The beer inside the keg weighs 124lbf and the container weighs 46lbf. The keg is placed at the top of ramp length L=8ft. from the back of your pickup truck to the ground and released. Find: 1. The rotational and linear speed of the keg at the bottom of the ramp. 2. The kinetic engery of th

Illuminance and intensity of light.

1). According to its package, a 100 watt light bulb emits 1140 lumens. For simplicity, assume the bulb provides isotropic illumination and ALL its emission is at 555 nm. A video camera is advertised as having "0.2 lux sensitivity", meaning it can record objects which receive at least this illuminance. In a dark room with no

Window Energy Transfer

A window has a glass surface area of 1.6x10^3 cm^2 and a thickness of 3.0 mm. a) Find the rate of energy transfer by conduction through the windows when the temperature of the inside surface of the glass is 70 degrees F and the outside temperature is 90 degrees F. b) Repeat for the same inside temperature and an outside t

Peak Electric Field in the Wave

A point source emits light energy uniformly in all directions at an average rate Po with a a single frequency f. Show that the peak electric field in the wave is given by: Eo = (µocPo/2 r2) (Everything is under the square root) I think we have to prove that the peak electric field is that equation but once again I am lost

Particle in a potential well

A particle of mass m moves in the potential V(x) = -g*delta(x) x>-a infinity x<-a (delta (x) = dirac delta function) a. Without worrying about continuity or boundary conditions, write down the general solution of the Schrodinger equation for a bound state (energy E<0) in regions( -a less than x les

Oscillations: The spring with varying force constant

Please see attachment. Thanks. --- Many real springs are more easily stretched than compressed. We can represent this by using different spring constants for and for . As an example, consider a spring that exerts the following restoring force: A mass on a frictionless, horizontal surface is attached to this spring,

Force of Friction and Gravitation Potential Energy

An electric winch pulls a 30.9 kg case of soap up a roller incline 3.01 m high in 3.15 seconds. The case starts from rest at the bottom and is moving 4.02 m/s at the top of the incline. The force of friction on the box is 39.4 N. a) What is the increase in gravitational potential energy of the box? b) Calculate the length

Angular Speed of Rotating Hoop

A string is wrapped several times around the rim of a small hoop with radius r and mass m . The free end of the string is held in place and the hoop is released from rest. Calculate the angular speed of the rotating hoop after it has descended a distance, h. (See attached file for diagram and figures)

Springs and Inclined Planes

1. A light horizontal spring has a force constant of k=100 N/m. A 2.00 kg block is pressed against one end of the spring, compressing it 0.100 m. When the block is released from rest it moves 0.250 m to the right of release position. Show that the coefficient of kinetic friction between the block and the horizontal surface is

Mechanical Energy: Block Projected up the Incline by Spring

A block with mass m = 2.00 kg is placed against a spring on a frictionless incline with angle = 30.0° (Figure 8-43). (The block is not attached to the spring.) The spring, with spring constant k = 19.9 N/cm, is compressed 24.0 cm and then released. How Far along the incline is the highest point from the release point? I

DC Circuits: Energy and Current

Assume that the length of an axon membrane of about 10 cm is excited by an action potential (length excited = nerve speed x pulse duration = 50 m/s x 2.0 ms = 10 cm). In the resting state, the outer surface of the axon wall is charged positively with K+ ions and the inner wall has an equal and opposite charge of negative org

Work and Kinetic Energy

The spring of a spring gun has force constant k = 400 N/m and negligible mass. The spring is compressed 6.00 cm and a ball with mass 0.0300 kg is placed in the horizontal barrel against the compressed spring. The spring is then released, and the ball is propelled out the barrel of the gun. The barrel is 6.00 cm long, so the ball

Kinetic Energy of a rotating bar

A thin, uniform 12.0-kg bar that is 2.00 m long rotates uniformly about a pivot at one end, making 5.00 complete revolutions every 3.00 seconds. What is the kinetic energy of this bar? (Hint: Different points in the bar have different speeds. Break the bar up into infinitesimal segments of mass dm and integrate to add up the

Charged particle fired at fixed charge

(See attached file for full problem description with proper symbols) --- A charge of -4.39 &#61549;C is fixed in place. From a horizontal distance of 0.0132 m, a particle of mass 9.78 x 10-3 kg and charge -8.74 &#61549;C is fired with an initial speed of 90.4 m/s directly toward the fixed charge. How far does the particle tr

Introduction to quantum mechanics past paper

2. Two possible wave functions for states of a particle, with definite energies E_1 and E_2 are: see attachement for equations. - Explain why these are called stationary states. - Write down a wavefunction for a non-stationary state for which the expectation value of the energy is (1/3*E_1) + 2/3*E_2). - Show that the p

Energy required to create a rabbit "out of thin air".

This figure indicates the energy required to conjure up the rabbit "out of thin-air". Evidently it takes more than energy, U=E, of the rabbit. Please explain, and also tell me why these energies are called "Free". In other words, why did scientists give them such a name? Which figure is correct or are they both correct ?

Helium Electrons

The energy levels for the helium ion He^+ are given by a formula similar to that for the hydrogen atom: 9.7 x 10^-18/n^2 J and the radii of the stationary electron orbits are at r_n=2.65 x 10^-11 n^2 What is the difference between a He^+ ion and a helium atom? Calculate the radii of the n=2 and n=3 orbits of He^+ and show