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# Speed of Light

The speed of light in a vacuum is a physical constant used in many areas of science. It is represented most commonly by the letter "c". The value of the speed of light in 299 792 458 m/s. The speed of light is the maximum speed which all energy or matter can travel.

The speed of light is also the speed of gravity. Particles and waves travel at the speed of light regardless of there motion of the source or the inertial frame of reference of the observer. Light can go through transparent materials, such as glass or air.. The ration between the speed of light and the speed at which light travels through the transparent material is called the refractive index, n, of the material. The equation of for refrctive index is N = c/v.

### Finding the Speed of an electron

The rest mass of an electron is  9.11x10^(-31) kg.  When the electron is in motion its mass becomes 15.2x10^(-31) kg. Find the speed of the electron.

### You and a friend are spending the weekend making up missed lab experiments. You are on to second semester material and are studying the electrostatic interaction of two charges.

You and a friend are spending the weekend making up missed lab experiments. You are on to second semester material and are studying the electrostatic interaction of two charges. You notice that two charges are exerting a certain force on one another. If the distance between two electric charges doubles, then the force they exert

### wave light theory

Does the wave theory of light explain more phenomena than the particle theory? Support your answer with specific details.

### Light Intensity: Momentum of Photons, Mirrors, and Velocity

The intensity of light with a mean wavelength of 854 nm falling on a solar sail is 140 watts/m^2. The sail is oriented perpendicular to the direction of the incoming light, in order to intercept as much light as possible. - What is the total momentum of the photons falling on 52000 m^2 of the sail every second? - If the sa

### An Analog (FM) cellular telephone system is analysed to find the Free space path loss, Noise power in the receiver and threshld link CNR

The frequency band 870 - 890 MHz is used for analog (FM) cellular telephone systems. A base station transmits a signal with a power of 1 watt to an antenna with a gain of 10 dB. The signal is received by a cell phone 2 km away with an antenna gain of 0 dB. a. For the path length of 2.0 km, calculate the free space path loss i

### Given that the speed of light, How far is earth from sun

Given that the speed of light is 2.998 m/s and that it takes 7 minutes for light from the sun to reach Earth, how far is Earth from the sun in miles? Recall that there are exactly 2.54 cm/in, exactly 12 in/ft and exactly 5,280 ft/mi. State your answer to the correct number of significant digits. Perform the same calculation usin

### Combined kinetic energy of the two-car system during collision

When cars are equipped with flexible bumpers, they will bounce off each other during low-speed collisions, thus causing less damage. In one such accident, a 1850 kg car traveling to the right at 1.40 m/s collides with a 1450 kg car going to the left at 1.10 m/s. Measurements show that the heavier car's speed just after the colli

### What is light, particles, waves or both

What is light? Is it a particle, wave, or both? Define the wave properties: period, wavelength, amplitude and frequency. What is c? How does c relate to wavelength and frequency?

### Problems involving the refraction of light

A light ray follows the indicated path through three different media, refracting at each of the two boundary surfaces as shown. Which of the following statements are true about the refraction of light in these cases (see attached file for diagram) 1. (T/F) if the index of refraction of medium #2 would change, then the r

### Frequency, Speed of Light, Wavelength in a Vacuum

The so-called "hydrogen alpha (Ha) line" is a specific wavelength of red light caused by excited atomic hydrogen. It is frequently used when studying the Sun. The wavelength of Ha is 656.3 nm, or 656.3*10-9 m. The speed of light in vacuum is 3*108 m/s. What is the frequency (in units of cycles per second, or 1/s) of Ha in va

### What is this critical speed?

A certain stop light stays yellow for 5 seconds before turning red. Suppose that your maximum deceleration from braking is 2 m/sec2. If you approach this light and it turns yellow, you normally have two options: If you are close enough to the light, you can continue on through at a constant speed before it turns red, while if

### Estimate the number of meters in one light year.

Light travels about 300,000,000 meters per second. A light year is the distance that light can travel in one year. Estimate the number of meters in one light year. Answer in Meters, then in both Kilometers and Miles. Can you show it step by step? What's the difference between a logarithm of a product and the product of logar

### Wave Function

1. A particle moving in one dimension between two rigid walls, (movement is perpendicular to the walls), separated by a distance L has the wave function: A*sin (Pi*x/L) Since the particle must remain between the walls what is the value of A? 2. A neutron has a Kinetic Energy of 10MeV. a) What size object is obje

### Optics of Light on a Pool

Looking for a distance below the pool and the time it takes the ray to travel from the swimming pool to the vertical wall. See attached for exact instruction and figure. In the diagram above, a ray from a spotlight strikes the surface of a swimming pool at an angle of 70° to the normal at a distance 4.00m from the pool ed

### Solving for Speed

1 - A swimmer wants to swim straight across a river with current flowing at a speed of v1 = 0.27 km/h. If the swimmer swims in still water with speed v2 = 0.81 km/h, at what angle should the swimmer point upstream from the shore and at what speed v will the swimmer swim across the river? 2 - In the 1887 experiment by Michels

### Calculate the de Broglie Wavelength for Various Objects

Calculate the de Broglie wavelength for each of the following. a) a proton with a velocity 80% of the speed of light b) an electron with a velocity 95% of the speed of light c) a 190 g ball with a velocity of 10 m/s

### Show the Final Formula to Solve for Each Variable

See the attached file. E = illumination r = distance I = intensity Illumination: Given the formula for E, show the final formula to solve for each of the following variables: r = I = ----------------------------------------------------------------------------------------------- n = index of refraction v = speed of

Radio waves travel with the speed of light, approximately 3.00 × 10^8 m/s in both vacuum and air. What are the wavelengths of the radio signals from (a) an FM station broadcasting at 97.5 MHz, (b) a standard AM station operating at 560 kHz, and (c) a shortwave station operating at 11,000 kHz?

### Set of miscellaneous problems on mechanics, light, sound, heat etc.

Question 1: Two people stand 3.0 m away from a large plane mirror and are 5.0 m apart from each other in a dark room. At what angle of incidence should one of them shine a flashlight on the mirror so that the reflected beam strikes the other person at the same height that the flashlight is held? Assume the person with the flashl

### Relativistic contraction of starships

(See attached file for full problem description with equations and diagrams) --- The Empire Strikes Back The starships of the Solar Federation are marked with the symbol of the Federation, a circle, whereas starships of the Denebian Empire are marked with the Empire's symbol, an ellipse whose major axis is n times its min

### Proton Velocity and Speed of Light

I need some help in determining what B is, when B=v/c and it is for a 20MeV Proton?

### The Mathematical Methods in Physical Sciences

1. The operating equation for a synchrotron in the relativistic range is qB = wm[1 - (wR)^2/c^2]^1/2 Where q and m are the charge and rest mass of the particle being accelerated, B is the magentic field strength, R is the orbit radius, q is the angular frequency, and c is the speed of light. If w and B are varied (all othe

### Simple motion problem

At the intersection of Texas Avenue and University Drive, a blue subcompact car of mass 950 kg traveling east on University collides with a maroon pickup truck of mass 1900 kg that is travelling north on Texas and ran a red light (Fig. 8-34 in the attached file). The two vehicles stick together as a result of the collision, and

### Physics

Two blocks of masses M and 3M are placed on a horizontal, frictionless surface. A light spring is attached to one of them, and the blocks are pushed together with the spring between them (Fig. P9.4). A cord initially holding the blocks together is burned; after this, the block of mass 3M moves to the right with a speed of 1.50 m

### Galileo's attempts to measure the speed of light with lanterns

(See attached file for full problem description) --- Galileo attempted to measure the speed of light by measuring the time elapsed between his opening a lantern and his seeing the return light from his assistant's lantern... ---

### Finding the Frequency of Photons of Light

If a photon of light has a wavelength of 540 nm, what is the frequency? I know speed of light is 3 x 10 to the 8th. Is the answer 5.55 x 10 to the 14th Hz?

### The Wavelength of Light

What is the wavelength of light that has a frequency of 1.20 x 1013s-1?

### Solving for the Index of Refraction

Question: The index of refraction of a diamond is 2.42. This means that a given wavelength of light travels a. 2.42 times faster in the diamond than it does in the vacuum b. 2.42 times faster in the diamond than it does in the air c. 2.42 times faster in the vacuum than it does in the diamond d. 2.42 times faster in the ai

### Psychological Stats

5. Road accident researchers were interested in the effectiveness of Red Light cameras that can photograph the number plates of cars if they pass through an intersection on a red light. Researchers arranged for speeds to be measured as cars entered intersections. There were two factors under consideration - Presence or Absenc

### Significant Effect or Not?

5. Road accident researchers were interested in the effectiveness of Red Light cameras that can photograph the number plates of cars if they pass through an intersection on a red light. Researchers arranged for speeds to be measured as cars entered intersections. There were two factors under consideration - Presence or Absenc