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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

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

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

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.

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-

Poynting vector from the antenna of a cell phone

An old analog hand-held cellular telephone operates in the 860 to 900 MHz band and has a power output of 0.600 W from an antenna 10.0 cm long. a. Find the average magnitude of the Poynting vector 4.00 cm from the antenna, at the location of a typical person's head. Assume that the antenna emits energy with cylindrical wave

Problem Set in Classical Physics

When a mass of 25.0 grams is suspended from a certain spring and lowered slowly until the spring stops stretching, the spring stretches 2.00 cm. What is the spring constant of the spring? a. 1.25 N/m b. 0.800 N/m c. 7.85 N/m d. 12.3 N/m A mass of 40.0 grams is attached to a vertical spring with a spring constant k = 2

Modern Physics with de-Broglie and Electron Microscope

1. Wavelength of particles a. Consider a dust particle of diameter d =1 micron, mass m= 10^-15 kg, and speed v = 1 mm/s. Calculate the de Broglie wavelength of the particle and compare with the particle's size. b. Now consider a thermal neutron, i.e, a neutron (m=1.67 x 10^-27 kg) with a speed corresponding to the average the

Velocity and Acceleration Positivity

I need help with the following two problems in the attachment. How do I tell if velocity and acceleration are positive, negative or zero? Please see the attached file. 1) The next figure above shows the velocity vectors corresponding to the upward motion of the power ball. Indicate whether its velocity and acceleration, respe

Dimensional Analysis, Vectors, etc.

Please see instructions on attachment. Please solve each and give a complete detailed step by step solution to solving each problem no matter how easy. I am trying to learn and not an expert. Give answer and way to solve. Adult student trying to make my way through all this and need your help! 1) A flat circular plate o

Wavelength of wave

The vertical displacement of a string is given by y(x,t) = (6.00mm) cos[(3.25m to the power of (-1)) x - (7.22 s to the power of (-1))t]. What is the wavelength of the wave?

Power/Current Required

An X-ray machine operates from a 220V supply. The machine power is 800W and the supply must also supply six 24W, 220V indicator lights. Please answer all questions with full explanations thankyou 1) What is the total power required? 2) What is the current drawn from the 220V supply? 3) A transformer with 250 turns in

Lenses/compound microscope

Hi. Can someone please show me how to do the following problem? "The medium-powered objective lens in a laboratory microscope has a focal length f-objective = 4.00 mm. (a) If this lens produces a lateral magnification of -40.0, whiat is the distance from the object to the objective lens? (b) What is the focal length of an ey


Sam, whose mass is 75 kg, takes off across level snow on his jet-powered skis. The skis have a thrust of 200 N and a coefficient of kinetic friction on snow of 0.1. Unfortunately, the skis run out of fuel after only 10 s. What is Sam's top speed? (in meters/second)How far has Sam traveled when he finally coasts to a stop? (in me

Various Physics Problems

Hi, I am having trouble doing these problems listed below. Please show me how to solve these problems for future reference. Thank you very much. 1. You are told that the volume of a sphere is given by V = pie d/4, where V is the volume and d is the diameter of the sphere. Is this equation dimensionally correct? (Use SI unit