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Anti-reflection coating

A linearly polarized plane wave of wavelength lembda, is travelling in air and ia incident normally on a plane sheet of glass. Show that the ratio of the reflected to the incident electric field amplitude is (n(glass)-n(air))/(n(glass)+n(air)) where n(air) and n(glass) are the refractive indices of ai

Fabry-Perot etalon

Could you please do the problem attached? Thank you. A Fabry-Perot etalon is used to resolve two spectral lines of equal intensity, and wavelengths of 670.776 nm and 670.791nm. The etalon plates have a reflectivity R = 0.85. Determine the minimum separation of the plates, d, for which the two lines are just resolved.

Complex Refractive Index and Power Reflection Coefficient

Show that the complex refractive index of a conducting medium can be expressed as n = λ0(1+i)/2 πδ and n = λ0(1-i)/2πδ where δ is the skin depth. Hence find the power reflection coefficient for an EM wave incident from free space on a good non-magnetic conductor at normal incidence. Show that the energy lost per unit area

average power and mechanical advantage of pulleys

1. Calculate the average power in kilowatts required to pull a car up a ramp if the amount of work is 250 kj over a period of 45 seconds. 2. Calculate the mechanical advantage of a group of pulleys used to raise an engine from a car. The engine is raised 1.2 m with the pulleys when 4.8 m of rope is pulled through the pulleys.

A plane electromagnetic wave is incident at angle on the boundary plane separating two non-magnetic media, with the electric vector in the plane of incidence. To show that wave reflected from the boundary has the same frequency as the incident wave and angle of reflection is equal to the angle of incidence. Also, derive an expression for the power reflection coefficient in this case.

A plane electromagnetic wave is incident at angle theta to the normal on the boundary plane separating two non-magnetic media with relative permitivities e1 and e2. For the case in which the electric vector is in the plane of incidence, show that any wave reflected from the boundary has the same frequency as the incident wave. S

The Poynting Vector and Power Dissipation

Consider the integral of the inwardly directed normal component of the Poynting vector over a surface S bounding a volume V of a linear, isotropic, homogeneous, conducting medium. Show that this quantity can be identified with the sum of the rate of change of the electromagnetic energy and the power dissipated when there is a fr

Voltages and power

In Europe the standard voltage in homes is 220V instead of the 120V used in the United States. Therefore a 100W European bulb would be intended for use with a 220V potential difference. 1) If you bring a 100W European bulb home to the United States, what should be its U.S. W power rating? 2) How much current in A will the 10

Transformers in a generating station

A generating station is producing 1.1 x 10^6 W of power that is to be sent to a small town located 8.0 km away. Each of the two wires that comprise the transmission line has a resistance per kilometer of length of 5.0 x 10^-2 ohms/km. (a) Find the power lost in heating the wires if the power is transmitted at 1100 V.

Light Diffraction

A source emits 531.62 nm and 532.82 nm light. 1.) What minimum number of lines is required for a grating that resolves the two wavelengths in the first-order spectrum? 2.) Determine the slit spacing for a grating 2.08 cm wide that has the required minimum number of lines. Answer in units of um. Please show all wor

Power Generation: Efficiency and the output.

Question 1 [2] In a coal fired power plant the output from the steam turbine is 500 MW in the form of shaft power. This is connected to an electric turbine with an efficiency of 96 %. The output voltage from the electric generator is 2000 V. What is the power output from the electric generator? What is the electric current

Sound intensity

A typical adult ear has a surface area of about 1.9 10-3 m2. The sound intensity during a normal conversation is about 3.6 10-6 W/m2 at the listener's ear. Assume the sound strikes the surface of the ear perpendicularly. How much power is intercepted by the ear?

Alternating Current Circuits

See attached file for full problem description. 18. A 120-V rms voltage at 1000 Hz is applied to a resistor and an inductor in series. If the impedance of this circuit is 110 ohms, what is the maximum value of the current? 19. A 200-ohm resistor, a 40.0-mH inductor and a 2.00-uF capacitor are connected in series with a 120

Power - How much time does it take to lift the piano?

A 2.40 * 10^2 kg piano is being lifted at a steady speed from ground level straight up to an apartment 10.0 m above the ground. The crane that is doing the lifting produces a steady power of 4.00 *10^2 W. How much time does it take to lift the piano?

Electrical Power

The instantaneous current and voltage in an electrical circuit are given by: i = Icos(50pi*t) v = Vcos(50*pit + pi/6) Determine an expression for the instantaneous power in the circuit p = iv, "AS THE SUM OF 2 COSINES" If I is 0.003 Amps and V is 5 volts, calculate the maximum value of p, giving the answer in watts corre

Electric Current - Internal Resistance of the Battery

1. A battery with 12-V emf has a terminal voltage of 11.4 V. When it delivers a delivers a current of 20 A to the starter of a car. What is the internal resistance r of the battery? A) how much emf is delivered but the battery above when it delivers a current of 20 A? (b) how much of this power is delivered to the starter?

Volume and Density of a Cylinder

1. A solid uranium cylinder weighs 91.53 N in air and 86.63 N when submerged in water. a. The volume of the cylinder is ----------mt^3 b. The density of uranium is---------kg/mt^3 2. On each heartbeat,about 70 cm^3 of blood is forced from a human heart at an average pressure of approx 105 mm Hg. a. If the heart beats 7

Determining the Voltage of an Unknown Battery in an Old Truck

There is an old truck that has a 6 or 12 volt battery in it which has very little charge left in it. The hood cannot be opened, so to charge the battery, someone uses 3 car batteries (12 volts each) which are placed in series. The reasoning is that if it is either a 6 volt or 12 volt battery that is in the truck, then the 3 batt

Power and Radius Calculations

1. The 50-lb load is hoisted by the pulley system and motor M. If the crate starts from rest and by constant acceleration attains a speed of 15 ft/s after rising 6 ft, determine the power that must be applied to the motor at this instant. The motor has an efficiency ε = 0.76. Neglect the mass of the pulleys and cable. 2. Ro

Observable in Heisenberg Picture

Consider the observable q_u = u_1q_1+u_2q_2+u_3q_3 , where the q_i are the Pauli matrices and where u = (u_1,u_2,u_3) in R^3 and the Hamiltonian is H = q3. Compute the observable (q_u)_H (t) derived from q_u in the Heisenberg picture.

Sound Intensity and Power

At a distance of 3.8 m from a siren, the sound intensity is 3.6 x 10^-2 W/m^2. Assuming that the siren radiates sound uniformly in all directions, how do you find the total power radiated?

Power Cycle for a Piston-Cylinder Device

A power cycle for a piston-cylinder device is described by the following four processes: 1→2 Isothermal compression from T1 = 300K, P1 = 100 kPa to P2 = 600 kPa. 2→3 Constant pressure heat addition until the temperature is T3 = 800K. 3→4 Isentropic expansion until the volume at state 4 equals the volume at state 1. 4

Engines and refrigerators

I have done an example to calculate the actual max efficiency of a power plant given the temperatures of both the hot and cold reservoirs. My book, however, tells me nothing about how to calculate any of the following questions. A power plant produces 1 GW of electricity, at an efficiency of 40%. (a) At what rate does th

Putting Prefixes in Order

Put these prefixes in order of increasing size. Put 1 for the smallest, 2 for the next largest, etc. 1. tera- 2. centi- 3. nano- 4. giga- 5. milli- 6. mega- 7. micro- 8. kilo-